Is uMatrix safe?

Clean risk

Control which websites can connect, load resources, run scripts, and use cookies through a point-and-click matrix.

This extension shows remote connections attempted by pages and lets you allow or block requests by destination domain and resource type, such as cookies, images, CSS, scripts, XHR, frames, and plugins. It uses scoped rules and can block requests before they leave the browser, with broad permissions to inspect and control web requests across sites.

Raymond HillFirefox Add-ons
0Risk
Who publishes it

Raymond Hill - no other listings under this identity, 4 shared hostnames

What this publisher told the store about itself, and the other listings that told it the same thing.

Publisher
Raymond Hill

Shared hosts - 4 hostnames

Hostnames hardcoded in this extension that few other listings call. That can mean one operator behind both, and it can equally mean a small shared vendor, so it is context rather than a conclusion. Hosts that many listings call are left out: they are services, not connections.

acid3.acidtests.org
Also called by 3 other listings, including uMatrix
grepular.com
Also called by 3 other listings, including uMatrix
winhelp2002.mvps.org
Also called by 3 other listings, including uMatrix, ScriptSafe
lucb1e.com
Also called by 5 other listings, including uMatrix

AI-generated. Findings may contain errors. Those marked Verified have been manually reviewed.

Publishers can request a review.

Updated 15 October 2026amo-613250