Simple Modify Headers - Extended Firefox

Simple Modify Headers - Extended

Rewrites HTTP request/response headers based on a rules table.

Features & Capabilities

Simple Modify Headers - Extended is a powerful Chrome extension that lets you rewrite HTTP request and response headers based on customizable rules. Originally forked from the Firefox extension simple-modify-headers (version 1.6.7), this tool provides enhanced functionality for web developers, testers, and privacy-focused users who want precise control over their HTTP headers. Users can create and manage a rules table to tailor how headers are modified for various browsing needs. Detailed change logs and usage instructions are available in the extension's README documentation. This extension is ideal for customizing browsing behavior, testing server responses, and improving privacy and security by manipulating headers on the fly.

User Growth & Download Statistics

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.
Developed by:
Warren Bank
Firefox Add-ons Store
https://addons.mozilla.org/firefox/addon/simple-modify-headers-extended/
Website:
https://github.com/warren-bank/crx-simple-modify-headers/issues

User Reviews

It works!
by fa*****, 2026-02-19

Works great, e.g. to remove Content-Security-Policy or X-Frame-Options that block embedding of other pages. UI could be more polished, but it still works even on Firefox Mobile. Attention: Uses full perl regular expressions, not match patterns.
by Ma*****, 2025-12-04
View all user reviews ›

Is Simple Modify Headers - Extended Safe?

Risk impact
Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

Simple Modify Headers - Extended requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
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Risk likelihood
Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

Simple Modify Headers - Extended is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
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  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
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Best Simple Modify Headers - Extended Alternatives

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