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Preview of JavaScript Permission Matrix

JavaScript Permission Matrix by Anon

This extension allows you to control JavaScript API permissions at per-script basis.

3.7 (3 reviews)3.7 (3 reviews)
1 User1 User
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Extension Metadata

About this extension
This extension lets you manage permissions for the use of JavaScript APIs both for entire sites or pages and for individual scripts. You can choose a combination of a script or page address together with an API name or some specific JavaScript functionality, and configure the permissions you consider necessary for that combination.

Example: on the same web page there are 2 different scripts. One allows you to edit images via the Canvas API. The other uses the same Canvas API to perform fingerprinting. The browser’s built-in mechanisms won’t let you allow Canvas to the first script and block it for the second. This extension will allow you to do that.

TL:DR; this extension may do the same things as WebAPI Manager or Web API blocker, but at per-script basis.
Rated 3.7 by 3 reviewers
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites
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Version
1.8.3.6
Size
70.5 KB
Last updated
4 months ago (Feb 28, 2026)
Related Categories
  • Privacy & Security
License
GNU General Public License v3.0 only
Version History
  • See all versions
Tags
  • anti tracker
  • privacy
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