Desktop:
- damn nice
- good Flatpak version playing everything
- all extensions work without weird restrictions
- only Forks that make sense, Librewolf and Tor Browser
- loads of search engines
- arkenfox user.js
- UserChrome.css, in theory, if it was easy to create one. Only SimpleMenuWizard currently to make it less rediculous to use
- also Thunderbird uses Firefox ESR, and its the only good Mail program I know
Mobile
- mull, prehardened
- support for a looot of addons using a custom Addon collection
- offline translations using FF Translations, literally the only app I know that does this and its so damn critical
- dark mode without tracking
- ublock, noscript
- lots of search engines possible
- privacy
I dont use Firefox as it comes on any device, as this is unusable. But with hardening its simply the most secure browser