firefox is a popular web browser. it's nice. i use it and it's pretty good. the problem is that it's full of shit by default.
and yet, every single day, i see this browser being shilled. and i hate it. no matter where i go, people advertise firefox as a privacy-friendly browser. but just because a browser is advertised as "privacy-friendly", doesn't necessarily mean it's true. i mean, yeah, firefox is open source but that doesn't necessarily mean it's secure or that it actually protects your fucking privacy or some shit. you really think an organisation would do that? just go on the internet and spread lies?
because firefox uses google analytics[1] to track you. it also has geolocation enabled by default. aside from this, it phones home upon startup, makes a bunch of requests to google every thirty minutes, and phones home about nearly every single interaction you have with its user interface[2]. not a great look if you ask me. while you can disable some of the telemetry through the GUI, for the rest of it, you're gonna have to get your hands dirty and dig around in about:config, something that not everyone is willing to do.
not to mention that firefox comes with google as the default search engine. so much for privacy. people recommend duckduckgo but that also glows. literally just use searx instead.
firefox does not have sane defaults. specifically for this post i made a brand new firefox profile so i can see what the default settings are. right upon startup we have shortcuts leading to amazon, facebook, reddit, youtube, twitter...god damn! google as the default search engine, again. recommend features/addons as you browse is turned on in the settings by default, asking to save passwords also enabled by default -- telemetry enabled by default under the privacy tab. going into about:config yields some interesting sights. again, geo.enabled is set to true by default, privacy.resistFingerprinting is off, and if you search for "telemetry", many of the items are set to true. yikes!
to avoid further incessant rambling, you can read more about this topic here.
because you can harden it. you can use a user.js to harden the browser settings. obviously that is out of the scope of this post, i'm not going to tell you which user.js to use, because i don't know what your needs are. i will say that you should probably create a new firefox profile if you'd like to test out some user.js configuration files.
there are forks of firefox, such as librewolf, GNU icecat, fuck, even tor browser. so if you don't want to use firefox itself, you can use a firefox-based browser instead. just be aware that some of them have issues of their own.
firefox comes with numerous shit defaults, but most of it can be mitigated/lessened. just harden your browser, for fuck's sake.