firefox menus not working

[N James Bridge]

Hi all

after installing the latest updates, all of Firefox's menus have stopped
working. Among other things, this makes it impossible to set preferences
or use bookmarks. I tried reinstalling it but it makes no difference.
Other apps (including Epiphany) seem not to be affected. 

According to yum.log, the possible cause may be one of

Jan 18 21:52:52 Updated: PackageKit-glib-0.6.11-2.fc14.x86_64
Jan 18 21:52:56 Updated: PackageKit-0.6.11-2.fc14.x86_64
Jan 18 21:52:57 Updated: PackageKit-yum-0.6.11-2.fc14.x86_64
Jan 18 21:52:58 Updated: PackageKit-gtk-module-0.6.11-2.fc14.x86_64
Jan 18 21:52:58 Updated: PackageKit-device-rebind-0.6.11-2.fc14.x86_64
Jan 18 21:52:59 Updated: 
                 PackageKit-command-not-found-0.6.11-2.fc14.x86_64
Jan 18 21:52:59 Updated: PackageKit-yum-plugin-0.6.11-2.fc14.x86_64
Jan 18 21:59:51 Updated: libattr-2.4.44-6.fc14.x86_64
Jan 18 21:59:52 Updated: gdbm-1.8.3-8.fc14.x86_64
Jan 18 21:59:53 Updated: attr-2.4.44-6.fc14.x86_64
Jan 18 21:59:54 Updated: wavpack-4.60.1-1.fc14.x86_64
Jan 18 22:00:36 Updated: selinux-policy-3.9.7-20.fc14.noarch
Jan 18 22:02:41 Updated: selinux-policy-targeted-3.9.7-20.fc14.noarch
Jan 18 22:02:42 Updated: gdbm-devel-1.8.3-8.fc14.x86_64
Jan 18 22:02:43 Updated: libattr-devel-2.4.44-6.fc14.x86_64
Jan 18 22:02:47 Updated: python-boto-1.9b-5.fc14.noarch

Any advice, please?

James Bridge