https://github.com/arkenfox/user.js There are hundreds of settings that can be configured to harden Firefox. A lot were upstreamed from the Tor Browser via the Tor Uplift project. The afforementioned user.js is well documented and the most well maintained that I'm aware of.

This is one of the leading reasons why I think Firefox is a better browser than competitors because they don't allow this level of customization without hacking on the source code, like say Brave does. However not even Brave or Ungoogled Chromium is hardened as much as Firefox is with this user.js.

it is like regular Firefox but really hard to install. It will also kill you if it crashes

> but the search is still anonymous

Is this verified though? I ask because Brave is known for some shady things, like pushing their alt coin or sneaking affiliate links into internet browsing.