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Preview of CORS Unbound Beta

CORS Unbound Beta by yobukodori

An official version of CORS Unbound is now available. Please use the stable release unless you specifically need to test upcoming changes. Bypass CORS and rewrite HTTP headers directly in the browser.

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About this extension
CORS Unbound is a Firefox extension that bypasses CORS restrictions and rewrites HTTP request/response headers directly inside the browser.
It is designed for local development, prototyping, automation, scraping, and advanced debugging — all without running a server.

Features

Automatic CORS Bypass
Injects the appropriate Access-Control-* headers into responses based on the browser’s own CORS request headers.

Header Rewriting
Add, modify, or remove request and response headers using a rule-based UI.

Rule System
Each rule defines:
  • Origin URLs (the page making the request)
  • Target URLs (the request destination)
  • Header Actions (set/remove)
  • Resource Types (xmlhttprequest, sub_frame, script, image, websocket, etc.)



Learn more at: https://github.com/yobukodori/cors-unbound
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Permissions and data

Required permissions:

  • Access your data for all web sites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
  • Homepage
  • Support site
Version
0.9.3
Size
48.2 kB
Last updated
11 days ago (22 Apr 2026)
Related Categories
  • Web Development
Licence
Mozilla Public Licence 2.0
Privacy Policy
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Version History
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