mobile: mixed image+file share skips the image size gate before base64 #229

Open
Open
mobile: mixed image+file share skips the image size gate before base64#229
Labels
bugSomething isn't working

Description

@rynfar
rynfar
opened on Sep 1, 2026

Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.

Problem

apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:

consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];

The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.

Trigger

Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.

Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].

Consequence

A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.

Amplifier

incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.

Related

The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.

Sketch

Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.

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      , '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" + '

      Skip to content
      mobile: mixed image+file share skips the image size gate before base64 #229
      Open
      Open
      mobile: mixed image+file share skips the image size gate before base64#229
      Labels
      bugSomething isn't working
      Description
      @rynfar
      rynfar
      opened on Sep 1, 2026
      Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
      Problem
      apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
      consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
      The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
      Trigger
      Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
      Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
      Consequence
      A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
      Amplifier
      incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
      Related
      The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
      Sketch
      Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
      Metadata
      Metadata
      Assignees
      No one assigned
        Labels
        bugSomething isn't working
        Type
        No type
        Projects
        No projects
          Milestone
          No milestone
          Relationships
          None yet
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          No branches or pull requests
          Issue actions
          
, '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
          mobile: mixed image+file share skips the image size gate before base64 #229
          Open
          Open
          mobile: mixed image+file share skips the image size gate before base64#229
          Labels
          bugSomething isn't working
          Description
          @rynfar
          rynfar
          opened on Sep 1, 2026
          Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
          Problem
          apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
          consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
          The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
          Trigger
          Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
          Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
          Consequence
          A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
          Amplifier
          incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
          Related
          The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
          Sketch
          Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
          Metadata
          Metadata
          Assignees
          No one assigned
            Labels
            bugSomething isn't working
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, '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
              mobile: mixed image+file share skips the image size gate before base64 #229
              Open
              Open
              mobile: mixed image+file share skips the image size gate before base64#229
              Labels
              bugSomething isn't working
              Description
              @rynfar
              rynfar
              opened on Sep 1, 2026
              Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
              Problem
              apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
              consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
              The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
              Trigger
              Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
              Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
              Consequence
              A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
              Amplifier
              incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
              Related
              The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
              Sketch
              Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
              Metadata
              Metadata
              Assignees
              No one assigned
                Labels
                bugSomething isn't working
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions
                  
, '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" + '

                  Skip to content
                  mobile: mixed image+file share skips the image size gate before base64 #229
                  Open
                  Open
                  mobile: mixed image+file share skips the image size gate before base64#229
                  Labels
                  bugSomething isn't working
                  Description
                  @rynfar
                  rynfar
                  opened on Sep 1, 2026
                  Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
                  Problem
                  apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
                  consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
                  The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
                  Trigger
                  Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
                  Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
                  Consequence
                  A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
                  Amplifier
                  incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
                  Related
                  The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
                  Sketch
                  Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
                  Metadata
                  Metadata
                  Assignees
                  No one assigned
                    Labels
                    bugSomething isn't working
                    Type
                    No type
                    Projects
                    No projects
                      Milestone
                      No milestone
                      Relationships
                      None yet
                      Development
                      No branches or pull requests
                      Issue actions
                      
, '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
                      mobile: mixed image+file share skips the image size gate before base64 #229
                      Open
                      Open
                      mobile: mixed image+file share skips the image size gate before base64#229
                      Labels
                      bugSomething isn't working
                      Description
                      @rynfar
                      rynfar
                      opened on Sep 1, 2026
                      Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
                      Problem
                      apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
                      consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
                      The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
                      Trigger
                      Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
                      Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
                      Consequence
                      A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
                      Amplifier
                      incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
                      Related
                      The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
                      Sketch
                      Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
                      Metadata
                      Metadata
                      Assignees
                      No one assigned
                        Labels
                        bugSomething isn't working
                        Type
                        No type
                        Projects
                        No projects
                          Milestone
                          No milestone
                          Relationships
                          None yet
                          Development
                          No branches or pull requests
                          Issue actions
                          
, '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
                          mobile: mixed image+file share skips the image size gate before base64 #229
                          Open
                          Open
                          mobile: mixed image+file share skips the image size gate before base64#229
                          Labels
                          bugSomething isn't working
                          Description
                          @rynfar
                          rynfar
                          opened on Sep 1, 2026
                          Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
                          Problem
                          apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
                          consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
                          The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
                          Trigger
                          Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
                          Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
                          Consequence
                          A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
                          Amplifier
                          incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
                          Related
                          The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
                          Sketch
                          Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
                          Metadata
                          Metadata
                          Assignees
                          No one assigned
                            Labels
                            bugSomething isn't working
                            Type
                            No type
                            Projects
                            No projects
                              Milestone
                              No milestone
                              Relationships
                              None yet
                              Development
                              No branches or pull requests
                              Issue actions
                              
, '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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                              mobile: mixed image+file share skips the image size gate before base64 #229
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                              Open
                              mobile: mixed image+file share skips the image size gate before base64#229
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                              bugSomething isn't working
                              Description
                              @rynfar
                              rynfar
                              opened on Sep 1, 2026
                              Found during adversarial review of #8237 adoption. Upstream code, adopted as-is.
                              Problem
                              apps/mobile/src/features/sharing/IncomingShareProvider.tsx:157-163:
                              consthasGenericFilePayload=payloads.some((p)=>["file","audio","video"].includes(p.shareType));constresolvedPayloads=!hasGenericFilePayload&&payloads.some((p)=>p.shareType==="image")
? awaitresolvedPayloadsForFiles()
: [];
                              The image branch's only size check before reading bytes is gated on that resolution (incoming-share-model.ts:396-403). With resolved === undefined the check is skipped and control reaches :409await input.fileReader.readBase64(uri) -> new File(uri).base64(), uncapped.
                              Trigger
                              Newly reachable because the same changeset widened registration: app.config.ts now uses singleShareMimeTypes: ["*/*"] / multipleShareMimeTypes: ["*/*"] on Android and supportsFileWithMaxCount: 8 on iOS.
                              Share one PDF + one large photo together from a file manager. Also fires on any image share where getResolvedSharedPayloadsAsync() throws, since the catch at :63-70 also returns [].
                              Consequence
                              A 300 MB image is materialised as a ~400 MB base64 string before the 10 MB check that would have rejected it.
                              Amplifier
                              incoming-share-inbox.ts:129 calls clearNativePayloads() only after buildDraft and writeDraft succeed, and iOS payloads persist in the App Group UserDefaults. If OOM kills the process rather than throwing a catchable error, refresh() re-ingests the identical payload on next launch — a launch loop with no in-app escape.
                              Related
                              The image branch trusts resolved.contentSize, which on Android is the sender's OpenableColumns.SIZE, not a measurement. The file branch was explicitly hardened against exactly this (incoming-share-model.ts:339-358 measures the persisted copy, test at incoming-share-model.test.ts:245). The image branch was not.
                              Sketch
                              Measure before reading, or gate the base64 read on a stat regardless of which branch resolved. The !hasGenericFilePayload && clause has no comment or test explaining its rationale — worth recovering that before changing it.
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