By tricking the browser with a X-Frame-Options
header, a sandboxed iframe could have presented a button that, if clicked by a user, would bypass restrictions to open a new window. This vulnerability affects Firefox < 127, Firefox ESR < 115.12, and Thunderbird < 115.12.
bugzilla.mozilla.org/show_bug.cgi?id=1888695
lists.debian.org/debian-lts-announce/2024/06/msg00000.html
lists.debian.org/debian-lts-announce/2024/06/msg00010.html
www.mozilla.org/security/advisories/mfsa2024-25/
www.mozilla.org/security/advisories/mfsa2024-26/
www.mozilla.org/security/advisories/mfsa2024-28/