Different techniques existed to obscure the fullscreen notification in Firefox and Focus for Android. These could have led to potential user confusion and spoofing attacks. *This bug only affects Firefox and Focus for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox for Android < 112 and Focus for Android < 112.
https://www.mozilla.org/security/advisories/mfsa2023-13/
https://bugzilla.mozilla.org/show_bug.cgi?id=1822305
https://bugzilla.mozilla.org/show_bug.cgi?id=1822298
https://bugzilla.mozilla.org/show_bug.cgi?id=1821906
https://bugzilla.mozilla.org/show_bug.cgi?id=1821576
https://bugzilla.mozilla.org/show_bug.cgi?id=1821155