Stick with Firefox for now.

Some FF forks like LibreWolf break sites because they are too strict. That isn't a critique, that's just how LibreWolf works and if your threat model requires it, go for it.

You can toggle the flags or use a userjs like arkenfox or betterfox. Eventually they might also enable these flags.

On Android I like Privacy Browser, but it takes getting used to (I like being logged out when I close the browser in case someone uses my phone).