@tennoseremel They signed an insane lock-in deal with Google, they collect an immense amount of data out of the box, the browser has inexcusably abysmal security no matter how much hardening is done, I could go on and on.

Don't use Firefox. Just don't.

Use hardened Chromium or Ungoogled Chromium. Ungoogled Chromium retains Chromium's stellar security model while still stripping it of any Google spyware or garbage.