Addon version numbers are not displayed next to their title in about:addons.The status bar does not include default items (zoom, full screen, screenshot).There are now additional preferences in about:preferences#privacy.DNS-over-HTTPS is now disabled by default - you must opt-in if you wish to use it.You can now toggle to populate extension information in about:addons.When you open a 'New Window', the address bar will now focus correctly.Modified 'Recent Activity' settings will now apply.about:preferences no longer renders incorrectly in certain situations.The Waterfox Classic styled theme 'Australis' is now available! You can switch to it in about:addons → 'Themes'.

If you started creating new sessions and logins in G4 and would like to have them still used, you can type about:config in the address bar, search for and toggle it to true once more. In G4.0.1 it is now OFF by default and your previous G3 session will be restored. This privacy focused preference only allows cookies, cache and local storage accessible by websites on the same domain and creates a separate session to when it is disabled. This was due to the setting of First Party Isolation to ON by default. ONLY if you upgraded from G3 → G4.0.0, you may have had your login sessions on various websites unavailable.

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