Title basically. I want to know what are the differences and which is the best in terms of privacy. Also, F-Droid says that Fennec tracks your activity, is it true?
Mull has an additional caveat as of 2023-09-14 ; password managers whitelist browsers for autofill, and 1Password hasn't whitelisted Mull yet. Bitwarden does. Others: I don't know.
Well, i know Fennec replaces Google with (i think its ddg by default). Otherwise i am not sure what it changes. I know Mull has even more privacy settings enabled by default.
If you want to be strict about privacy, in F-Droid turn off all anti-features and you'll see there is no version of Firefox available to install. You have to make compromises if yo want to install any off-shoot of Firefox.