Thanks for reporting. The upstream issue was marked as a duplicate of https://bugzilla.mozilla.org/show_bug.cgi?id=1311329, so I've taken the liberty of adding a bug watch for this issue.
Looks like the actual issue occurs because the specification has changed, but the test hasn't been updated, see discussion on the upstream issue for details. ** Bug watch added: Mozilla Bugzilla #1311329 https://bugzilla.mozilla.org/show_bug.cgi?id=1311329 ** Also affects: firefox via https://bugzilla.mozilla.org/show_bug.cgi?id=1311329 Importance: Unknown Status: Unknown -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1690006 Title: Firefox fails acid3.acidtests.org To manage notifications about this bug go to: https://bugs.launchpad.net/firefox/+bug/1690006/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs