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fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159

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Mar 25, 2026
Merged

fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
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brkalow/fix-proxy-content-encoding

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@brkalowbrkalow commented Mar 24, 2026•
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Summary

  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js

Test plan

  • Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  • Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  • Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  • Run @clerk/backend unit tests

🤖 Generated with Claude Code

Summary by CodeRabbit

  • Bug Fixes

    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.

  • Tests

    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.

  • Chores

    • Added a patch release entry describing the fix.

@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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🦋 Changeset detected

Latest commit: 8889621

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Review profile: ASSERTIVE

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Run ID: bf197657-634c-4d7a-8ded-47a493974bf2

📥 Commits

Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.

📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough

Walkthrough

The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.

🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

✏️ Tip: You can configure your own custom pre-merge checks in the settings.

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@clerk/backend

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@clerk/chrome-extension

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@clerk/clerk-js

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@clerk/dev-cli

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@clerk/expo

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@clerk/expo-passkeys

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@clerk/express

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@clerk/fastify

npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono

npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations

npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs

npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt

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@clerk/react

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@clerk/react-router

npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared

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@clerk/tanstack-react-start

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@clerk/testing

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@clerk/ui

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@clerk/upgrade

npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue

npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621

@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow commented Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts Outdated
@brkalow
brkalow merged commit 0288931 into mainMar 25, 2026
44 checks passed
@brkalow
brkalow deleted the brkalow/fix-proxy-content-encoding branch March 25, 2026 02:32
@clerk-cookieclerk-cookie mentioned this pull request Mar 25, 2026
Merged
wobsoriano pushed a commit that referenced this pull request Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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@brkalow@wobsoriano
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fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Conversation
@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Mar 24, 2026•

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edited

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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
@coderabbitai
coderabbitaiBot
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Mar 24, 2026•

edited

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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
⚙️ Run configuration
Configuration used: Repository YAML (base), Organization UI (inherited)
Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
Comment @coderabbitai help to get the list of available commands and usage tips.
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@clerk/agent-toolkit
npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
npm i https://pkg.pr.new/@clerk/shared@8159

@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
npm i https://pkg.pr.new/@clerk/testing@8159

@clerk/ui
npm i https://pkg.pr.new/@clerk/ui@8159

@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow
commented
Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts
Outdated

@brkalow
brkalow
merged commit 0288931
into
mainMar 25, 2026

44 checks passed

@brkalow
brkalow
deleted the

brkalow/fix-proxy-content-encoding

branch
March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
 Merged

wobsoriano pushed a commit
that referenced
this pull request
Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Conversation
@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Mar 24, 2026•

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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Mar 24, 2026•

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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
⚙️ Run configuration
Configuration used: Repository YAML (base), Organization UI (inherited)
Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
Comment @coderabbitai help to get the list of available commands and usage tips.
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@clerk/agent-toolkit
npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
npm i https://pkg.pr.new/@clerk/shared@8159

@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
npm i https://pkg.pr.new/@clerk/testing@8159

@clerk/ui
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@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow
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Mar 24, 2026
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Comment threadpackages/backend/src/proxy.ts
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deleted the

brkalow/fix-proxy-content-encoding

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March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
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Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
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observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
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brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
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brkalow/fix-proxy-content-encoding
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@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
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Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
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npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
npm i https://pkg.pr.new/@clerk/shared@8159

@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
npm i https://pkg.pr.new/@clerk/testing@8159

@clerk/ui
npm i https://pkg.pr.new/@clerk/ui@8159

@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow
commented
Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts
Outdated

@brkalow
brkalow
merged commit 0288931
into
mainMar 25, 2026

44 checks passed

@brkalow
brkalow
deleted the

brkalow/fix-proxy-content-encoding

branch
March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
 Merged

wobsoriano pushed a commit
that referenced
this pull request
Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Conversation
@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Mar 24, 2026•

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ProjectDeploymentActionsUpdated (UTC)
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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
⚙️ Run configuration
Configuration used: Repository YAML (base), Organization UI (inherited)
Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
Comment @coderabbitai help to get the list of available commands and usage tips.
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npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
npm i https://pkg.pr.new/@clerk/shared@8159

@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
npm i https://pkg.pr.new/@clerk/testing@8159

@clerk/ui
npm i https://pkg.pr.new/@clerk/ui@8159

@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow
commented
Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts
Outdated

@brkalow
brkalow
merged commit 0288931
into
mainMar 25, 2026

44 checks passed

@brkalow
brkalow
deleted the

brkalow/fix-proxy-content-encoding

branch
March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
 Merged

wobsoriano pushed a commit
that referenced
this pull request
Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Conversation
@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Review profile: ASSERTIVE
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Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
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npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
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@clerk/dev-cli
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@clerk/expo
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@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
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@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
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@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
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@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
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@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
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@clerk/ui
npm i https://pkg.pr.new/@clerk/ui@8159

@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
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Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts
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44 checks passed

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brkalow/fix-proxy-content-encoding

branch
March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
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that referenced
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Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
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function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
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})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
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brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
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@brkalow
@brkalowbrkalow
commented
Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
⚙️ Run configuration
Configuration used: Repository YAML (base), Organization UI (inherited)
Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
Comment @coderabbitai help to get the list of available commands and usage tips.
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@clerk/agent-toolkit
npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

@clerk/shared
npm i https://pkg.pr.new/@clerk/shared@8159

@clerk/tanstack-react-start
npm i https://pkg.pr.new/@clerk/tanstack-react-start@8159

@clerk/testing
npm i https://pkg.pr.new/@clerk/testing@8159

@clerk/ui
npm i https://pkg.pr.new/@clerk/ui@8159

@clerk/upgrade
npm i https://pkg.pr.new/@clerk/upgrade@8159

@clerk/vue
npm i https://pkg.pr.new/@clerk/vue@8159

commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
brkalow
commented
Mar 24, 2026
View reviewed changes
Comment threadpackages/backend/src/proxy.ts
Outdated

@brkalow
brkalow
merged commit 0288931
into
mainMar 25, 2026

44 checks passed

@brkalow
brkalow
deleted the

brkalow/fix-proxy-content-encoding

branch
March 25, 2026 02:32
@clerk-cookieclerk-cookie
mentioned this pull request
Mar 25, 2026
 Merged

wobsoriano pushed a commit
that referenced
this pull request
Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
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style = document.createElement('style');
style.id = 'universal-dark-mode-style';
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filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
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filter: invert(1) hue-rotate(180deg) !important;
}
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[data-theme="light"], [data-theme="light"],
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filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
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var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
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observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
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} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
fix(backend): prevent Content-Encoding mismatch in proxy responses by brkalow · Pull Request #8159 · clerk/javascript · GitHub
Skip to content
fix(backend): prevent Content-Encoding mismatch in proxy responses - #8159
Merged
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
Mar 25, 2026
Merged
fix(backend): prevent Content-Encoding mismatch in proxy responses#8159
brkalow merged 4 commits into
mainfrom 
brkalow/fix-proxy-content-encoding
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@brkalow
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Mar 24, 2026•

edited by coderabbitai
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Summary
  • Adds Accept-Encoding: identity on outbound proxy requests to avoid a double compression pass (FAPI compresses → fetch decompresses → edge re-compresses)
  • Defensively strips Content-Encoding and Content-Length from proxied responses since fetch() auto-decompresses the body, making those headers inaccurate
  • Fixes ERR_CONTENT_DECODING_FAILED errors when loading proxied assets like clerk.browser.js
Test plan
  •  Verify proxied JS assets (e.g. /__clerk/npm/@clerk/clerk-js/.../clerk.browser.js) load without ERR_CONTENT_DECODING_FAILED
  •  Verify proxy still works for API requests (/__clerk/v1/client, etc.)
  •  Verify OAuth redirect flows still work through the proxy (Location header rewriting)
  •  Run @clerk/backend unit tests
🤖 Generated with Claude Code
Summary by CodeRabbit
  • Bug Fixes
    • Prevented content-decoding errors by requesting uncompressed upstream responses and stripping Content-Encoding and Content-Length from proxied responses.
  • Tests
    • Added tests ensuring outgoing requests request uncompressed content and that compression/length headers are removed from proxied responses.
  • Chores
    • Added a patch release entry describing the fix.
@brkalow@claude
fix(backend): prevent Content-Encoding mismatch in proxy responses
41cf658
fetch() auto-decompresses response bodies but may leave Content-Encoding
and Content-Length headers intact, causing ERR_CONTENT_DECODING_FAILED
in the browser. Fix with two layers:
1. Request `Accept-Encoding: identity` upstream to avoid a double
compression pass (FAPI → fetch decompresses → edge re-compresses)
2. Defensively strip Content-Encoding and Content-Length from responses
since servers may ignore the identity hint
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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🦋 Changeset detected
Latest commit: 8889621
The changes in this PR will be included in the next version bump.
This PR includes changesets to release 11 packages
NameType
@clerk/backendPatch
@clerk/agent-toolkitPatch
@clerk/astroPatch
@clerk/expressPatch
@clerk/fastifyPatch
@clerk/honoPatch
@clerk/nextjsPatch
@clerk/nuxtPatch
@clerk/react-routerPatch
@clerk/tanstack-react-startPatch
@clerk/testingPatch
Not sure what this means? Click here to learn what changesets are.
Click here if you're a maintainer who wants to add another changeset to this PR
@brkalow@claude
chore(repo): add changeset for proxy Content-Encoding fix
daa90b5
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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No actionable comments were generated in the recent review. 🎉
ℹ️ Recent review info
⚙️ Run configuration
Configuration used: Repository YAML (base), Organization UI (inherited)
Review profile: ASSERTIVE
Plan: Pro
Run ID: bf197657-634c-4d7a-8ded-47a493974bf2
📥 Commits
Reviewing files that changed from the base of the PR and between 17bd235 and 8889621.
📒 Files selected for processing (1)
  • packages/backend/src/proxy.ts
📝 Walkthrough
Walkthrough
The PR sets Accept-Encoding: identity on upstream requests, adds RESPONSE_HEADERS_TO_STRIP to drop content-encoding and content-length from proxied responses, and extends hop-by-hop header filtering to include those headers. The proxy now constructs a Response object and explicitly deletes content-encoding and content-length from its headers before returning. Two tests were added: one asserting the outgoing request uses Accept-Encoding: identity, and another asserting Content-Encoding and Content-Length are removed from upstream responses. A changeset for a patch release was added.
🚥 Pre-merge checks | ✅ 3
✅ Passed checks (3 passed)
Check nameStatusExplanation
Description Check✅ PassedCheck skipped - CodeRabbit’s high-level summary is enabled.
Title check✅ PassedThe title accurately summarizes the main change: preventing Content-Encoding mismatches in proxy responses by requesting uncompressed responses and stripping encoding headers.
Docstring Coverage✅ PassedDocstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
✏️ Tip: You can configure your own custom pre-merge checks in the settings.
Comment @coderabbitai help to get the list of available commands and usage tips.
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@clerk/agent-toolkit
npm i https://pkg.pr.new/@clerk/agent-toolkit@8159

@clerk/astro
npm i https://pkg.pr.new/@clerk/astro@8159

@clerk/backend
npm i https://pkg.pr.new/@clerk/backend@8159

@clerk/chrome-extension
npm i https://pkg.pr.new/@clerk/chrome-extension@8159

@clerk/clerk-js
npm i https://pkg.pr.new/@clerk/clerk-js@8159

@clerk/dev-cli
npm i https://pkg.pr.new/@clerk/dev-cli@8159

@clerk/expo
npm i https://pkg.pr.new/@clerk/expo@8159

@clerk/expo-passkeys
npm i https://pkg.pr.new/@clerk/expo-passkeys@8159

@clerk/express
npm i https://pkg.pr.new/@clerk/express@8159

@clerk/fastify
npm i https://pkg.pr.new/@clerk/fastify@8159

@clerk/hono
npm i https://pkg.pr.new/@clerk/hono@8159

@clerk/localizations
npm i https://pkg.pr.new/@clerk/localizations@8159

@clerk/nextjs
npm i https://pkg.pr.new/@clerk/nextjs@8159

@clerk/nuxt
npm i https://pkg.pr.new/@clerk/nuxt@8159

@clerk/react
npm i https://pkg.pr.new/@clerk/react@8159

@clerk/react-router
npm i https://pkg.pr.new/@clerk/react-router@8159

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commit: 8889621
@brkalow@claude
fix(backend): explicitly delete encoding headers after Response const…
17bd235
…ruction
Some runtimes (e.g. Node 20) may re-add Content-Length when constructing
a Response from a ReadableStream body. Delete Content-Encoding and
Content-Length explicitly after construction to ensure they're stripped.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
brkalow
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Mar 24, 2026
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Comment threadpackages/backend/src/proxy.ts
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brkalow/fix-proxy-content-encoding

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Mar 26, 2026
@brkalow@claude@wobsoriano
fix(backend): prevent Content-Encoding mismatch in proxy responses (#…
6081fae
…8159)
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
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