The bugzilla bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1432966 https://bugzilla.mozilla.org/show_bug.cgi?id=1432966 It sounds like Firefox sometimes in

The bugzilla bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1432966 https://bugzilla.mozilla.org/show_bug.cgi?id=1432966 It sounds like Firefox sometimes injects untrusted HTML into the browser chrome.