Oh god, JS version of gmail is unusable on firefox.
Takes minutes(!) to load(multiple powerful machines - i7 3770k, i5 6th gen and i7 7700, tested on fresh OS installs of both Win10 and Ubuntu) - it fakes loaded status usually by displaying your last viewed page - which is very annoying as it has no loading bar nor a throbber.
It is horrible when you are waiting for 2FA code in email, or when resetting a password.
Takes minutes(!) to load(multiple powerful machines - i7 3770k, i5 6th gen and i7 7700, tested on fresh OS installs of both Win10 and Ubuntu) - it fakes loaded status usually by displaying your last viewed page - which is very annoying as it has no loading bar nor a throbber.
It is horrible when you are waiting for 2FA code in email, or when resetting a password.