Firefox Privacy: 2021 Update

A lot changed between 2019 and now, not least in regards to Firefox. Since our last post, Mozilla has improved privacy with Enhanced Tracking Protection (ETP). Earlier this year Mozilla introduced Total Cookie Protection (Dynamic First Party Isolation dFPI). This was then further tightened with Enhanced Cookie Clearing. We’re also looking very forward to Site Isolation (code named Fission) being enabled by default in the coming releases.

This is a companion discussion topic for the original entry at

As far as I know, the website doesn’t recommend extensions: uBlock Origin is listed at the discretion of the reader. I’m not certain, but it might be for this reason.

Notwithstanding Privacy Guides’s position, which uMatrix functionality are you struggling to replicate with uBlock Origin and Firefox’s settings? The GitHub wiki provides extensive documentation for its static filter, for example.

If you’re referring to the toolbar menu, uBlock Origin actually lets you filter a lot more than just domains (you have to tick “I am an advanced user” in the settings menu).

Regardless, this seems like an issue of convenience rather than functionality—unless there’s a particular case that uBlock Origin and Firefox’s settings can’t reproduce.

You can also use the select icon and block specific elements on the page with uBlock Origin

Sorry: I’m probably not explaining it very well.

The toolbar UI allows you to filter XHR (via third-party, although the static filter offers more specific control); images; cosmetic elements, JavaScript; media; iframes; and others—like remote fonts, or even just all “extra” content. The filters can be applied on a domain basis (and it’s not restricted to apex domains, I should mention), globally, or with specific rules.

The GitHub Wiki has much more thorough documentation which might do a better job of explaining its functionality than I can! :sweat_smile:

True. However,

I hope my explanation and uBlock Origin’s wiki clarifies the reasoning behind Arkenfox’s statement to prefer uBlock Origin over uMatrix! :smile:

The only advantage in functionality of uMatrix over uBO is blocking cookies (or more precisely HTTP Cookie header, cookies are better handled by browser, rather than add-ons).

The other things are just about convenience (actually you can filter connection types with the whole URLs via uBO’s logger, so you don’t need to type).