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Preview of PlainHeaders – Modify Headers, Header Editor

PlainHeaders – Modify Headers, Header Editor by Jacque

Modify HTTP request and response headers: add, change or remove them per site or per tab. Profiles, presets, ModHeader-format import. No tracking.

Available on Firefox for Android™Available on Firefox for Android™
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About this extension
PlainHeaders is a small, honest HTTP header editor for developers.
• Set, append or remove request and response headers (Authorization, CORS, CSP, User-Agent, X-Forwarded-For…)
• One-click presets: CORS allow-all, remove CSP / X-Frame-Options, disable caching, mobile user agent
• "This tab only": lock a profile to the current tab so other tabs stay untouched
• Profiles you can switch in one click; pause everything instantly; badge shows active header count
• Import ModHeader-format JSON exports or PlainHeaders backups; export anytime
• Private by design: no analytics, no ads, no remote code. Host access is requested per site when you click "Enable on this site" — never all sites at install. It makes no network requests of its own.
Pro (planned for a later update, optional one-time purchase): several profiles at once, URL filters and redirects. The free tier has no header limit.
Built with AI assistance; maintained by an independent developer.
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Required permissions:

  • Block content on any page

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
0.1.0
Size
21.58 KB
Last updated
24 days ago (Oct 1, 2026)
Related Categories
  • Web Development
License
MIT License
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