fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577

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Pavel Feldman (pavelfeldman) merged 2 commits into
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copilot/fix-screenshot-base64-response
May 5, 2026
Merged

fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom
copilot/fix-screenshot-base64-response

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CopilotAI commented May 1, 2026•
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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.

Changes

  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.

Behavior

filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

CopilotAI linked an issue May 1, 2026 that may be closed by this pull request
browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided microsoft/playwright-mcp#1581
Closed
@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI changed the title [WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory) mentioned this pull request May 5, 2026
Closed
@pavelfeldman
Pavel Feldman (pavelfeldman) marked this pull request as ready for review May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman) merged commit 07ad0ed into mainMay 5, 2026
15 of 17 checks passed
@pavelfeldman
Pavel Feldman (pavelfeldman) deleted the copilot/fix-screenshot-base64-response branch May 5, 2026 23:37
This was referenced May 7, 2026
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@markb-trustifi

markb-trustifi commented Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.

In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.

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Reviewers

@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes
+1 more reviewer
@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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@yury-sYury Semikhatsky (yury-s)

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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided

4 participants

@markb-trustifi@pavelfeldman@yury-s
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
Merged
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
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CopilotAI
commented
May 1, 2026•

edited

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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
If you need me to access, download, or install something from one of these locations, you can either:
CopilotAI
linked an issue
May 1, 2026
that may be
closed
by this pull request


browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

Closed

@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
 Closed

@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
into
mainMay 5, 2026

15 of 17 checks passed

@pavelfeldman
Pavel Feldman (pavelfeldman)
deleted the

copilot/fix-screenshot-base64-response

branch
May 5, 2026 23:37

This was referenced May 7, 2026

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@markb-trustifi
markb-trustifi
commented
Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

+1 more reviewer

@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


4 participants

@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
Merged
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
Conversation
CopilotAI
commented
May 1, 2026•

edited

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Contributor
When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
If you need me to access, download, or install something from one of these locations, you can either:
CopilotAI
linked an issue
May 1, 2026
that may be
closed
by this pull request


browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

Closed

@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
 Closed

@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
into
mainMay 5, 2026

15 of 17 checks passed

@pavelfeldman
Pavel Feldman (pavelfeldman)
deleted the

copilot/fix-screenshot-base64-response

branch
May 5, 2026 23:37

This was referenced May 7, 2026

Closed


Closed

@markb-trustifi
markb-trustifi
commented
Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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Reviewers

@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

+1 more reviewer

@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
Reviewers whose approvals may not affect merge requirements

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@yury-sYury Semikhatsky (yury-s)
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


4 participants

@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
Merged
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
Conversation
CopilotAI
commented
May 1, 2026•

edited

Loading

Copy link


Copy Markdown

Contributor
When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
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CopilotAI
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

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@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
 Closed

@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
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Pavel Feldman (pavelfeldman)
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May 5, 2026 23:37

This was referenced May 7, 2026

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@markb-trustifi
markb-trustifi
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Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

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@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


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@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
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Pavel Feldman (pavelfeldman) merged 2 commits into
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copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
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CopilotAI
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May 1, 2026•

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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
If you need me to access, download, or install something from one of these locations, you can either:
CopilotAI
linked an issue
May 1, 2026
that may be
closed
by this pull request


browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

Closed

@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
 Closed

@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
into
mainMay 5, 2026

15 of 17 checks passed

@pavelfeldman
Pavel Feldman (pavelfeldman)
deleted the

copilot/fix-screenshot-base64-response

branch
May 5, 2026 23:37

This was referenced May 7, 2026

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@markb-trustifi
markb-trustifi
commented
Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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Reviewers

@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

+1 more reviewer

@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


4 participants

@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
Merged
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
Conversation
CopilotAI
commented
May 1, 2026•

edited

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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
If you need me to access, download, or install something from one of these locations, you can either:
CopilotAI
linked an issue
May 1, 2026
that may be
closed
by this pull request


browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

Closed

@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
 Closed

@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
into
mainMay 5, 2026

15 of 17 checks passed

@pavelfeldman
Pavel Feldman (pavelfeldman)
deleted the

copilot/fix-screenshot-base64-response

branch
May 5, 2026 23:37

This was referenced May 7, 2026

Closed


Closed

@markb-trustifi
markb-trustifi
commented
Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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Reviewers

@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

+1 more reviewer

@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
Reviewers whose approvals may not affect merge requirements

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@yury-sYury Semikhatsky (yury-s)
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Successfully merging this pull request may close these issues.

browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


4 participants

@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
Merged
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
May 5, 2026
Merged
fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
mainfrom 
copilot/fix-screenshot-base64-response
Conversation
CopilotAI
commented
May 1, 2026•

edited

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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

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@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
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@pavelfeldman
Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
merged commit 07ad0ed
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@markb-trustifi
markb-trustifi
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Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

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@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


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@markb-trustifi@pavelfeldman@yury-s

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot - #40577
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Pavel Feldman (pavelfeldman) merged 2 commits into
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copilot/fix-screenshot-base64-response
May 5, 2026
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fix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshot#40577
Pavel Feldman (pavelfeldman) merged 2 commits into
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copilot/fix-screenshot-base64-response
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CopilotAI
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May 1, 2026•

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When browser_take_screenshot is called with an explicit filename, the screenshot was saved to disk and also embedded as base64 in the MCP response — a redundant payload that can consume 70–80% of an LLM's context window for a single screenshot.
Changes
  • screenshot.ts: Guard registerImageResult behind !params.filename — image is only embedded in the MCP response when the caller did not provide an explicit destination filename.
awaitresponse.addFileResult(resolvedFile,data);if(!params.filename)awaitresponse.registerImageResult(data,fileType);
  • screenshot.spec.ts: Updated browser_take_screenshot (filename: "output.png") test to expect only a text result (no image attachment) when an explicit filename is provided.
Behavior
filename paramImage in MCP response
omitted✅ included (LLM can see it)
'' (empty string)✅ included (treated as auto-generate)
"output.png"❌ omitted (file saved to disk only)
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
  • accounts.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • clients2.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
  • safebrowsingohttpgateway.googleapis.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
  • www.google.com
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8030 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-element--chrome/ms-playwright/mcp-chrome-84785ae --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,16395666331397327551,10646199456832461908,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /proc/self/exe /proc/self/exe --type=utility --utility-sub-type=network.mojom.NetworkService --lang=en-US --service-sandbox-type=none --disable-dev-shm-usage --use-angle=swiftshader-webgl --mute-audio --crashpad-handler-pid=8031 --enable-crash-reporter=, --noerrdialogs --user-data-dir=/home/REDACTED/work/playwright/playwright/test-results/screenshot-browser-take-screenshot-viewport--chrome/ms-playwright/mcp-chrome-965a9ec --change-stack-guard-on-fork=enable --shared-files=v8_context_snapshot_data:100 --field-trial-handle=3,i,3823535755795048791,9872173523762485258,262144 --enable-features=CDPScreenshotNewSurface --disable-features=AutoDeElevate,AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,OptimizationHints,PaintHolding,Rend (dns block)
    • Triggering command: /opt/google/chrome/chrome /opt/google/chrome/chrome --disable-field-trial-config --disable-REDACTED-networking --disable-REDACTED-timer-throttling --disable-REDACTEDing-occluded-windows --disable-back-forward-cache --disable-breakpad --disable-client-side-phishing-detection --disable-component-extensions-with-REDACTED-pages --disable-component-update --no-default-browser-check --disable-default-apps --disable-dev-shm-usage --disable-edgeupdater --disable-features=AvoidUnnecessaryBeforeUnloadCheckSync,BoundaryEventDispatchTracksNodeRemoval,DestroyProfileOnBrowserClose,DialMediaRouteProvider,GlobalMediaControls,HttpsUpgrades,LensOverlay,MediaRouter,PaintHolding,ThirdPartyStoragePartitioning,Transl (dns block)
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CopilotAI
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May 1, 2026
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided
microsoft/playwright-mcp#1581

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@yury-s
fix(mcp): skip image in MCP response when filename is explicitly prov…
c1d458e
…ided for browser_take_screenshot
Agent-Logs-Url: https://github.com/microsoft/playwright/sessions/c5b0b096-f441-411a-9107-44373adcb55f
Co-authored-by: yury-s <9798949+yury-s@users.noreply.github.com>
CopilotAI
changed the title
[WIP] Fix MCP response to exclude base64 image when filename is providedfix(mcp): skip base64 image response when filename is explicitly provided to browser_take_screenshotMay 1, 2026
@MeroZemoryJio Kim (MeroZemory)
mentioned this pull request
May 5, 2026
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Pavel Feldman (pavelfeldman)
marked this pull request as ready for review
May 5, 2026 23:15
@pavelfeldman
Pavel Feldman (pavelfeldman)
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Pavel Feldman (pavelfeldman)
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May 5, 2026 23:37

This was referenced May 7, 2026

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@markb-trustifi
markb-trustifi
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Jun 3, 2026

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The fix in https://github.com/microsoft/playwright/blob/main/packages/playwright-core/src/tools/backend/screenshot.ts#L70 broke existing agentic flow.
In many cases AI agents ask for screenshots with automatically generated filenames. Now, the screenshot requests will not work because it will not return an image output to LLM.
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@pavelfeldmanPavel Feldman (pavelfeldman)pavelfeldman approved these changes

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@yury-sYury Semikhatsky (yury-s)yury-s approved these changes
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browser_take_screenshot: image still returned as base64 in MCP response when filename param is provided


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