I think I have tracked the bug down to the "Global Menu Bar integration" extension, aka firefox-globalmenu. When I disable this, the menus work correctly.
Again, I never had this problem before Firefox 14. firefox-globalmenu: Installed: 15.0.1+build1-0ubuntu0.12.04.1 Candidate: 15.0.1+build1-0ubuntu0.12.04.1 Version table: *** 15.0.1+build1-0ubuntu0.12.04.1 0 500 http://us.archive.ubuntu.com/ubuntu/ precise-updates/main i386 Packages 500 http://security.ubuntu.com/ubuntu/ precise-security/main i386 Packages 100 /var/lib/dpkg/status 11.0+build1-0ubuntu4 0 500 http://us.archive.ubuntu.com/ubuntu/ precise/main i386 Packages 7.0.1+build1+nobinonly-0ubuntu2 0 500 http://archive.ubuntu.com/ubuntu/ oneiric/main i386 Packages -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1020198 Title: Drop downs, drag-and-drop and right click menus don't work with Mozilla ff/tb 14.0 Status in “firefox” package in Ubuntu: Confirmed Status in “unity-2d” package in Ubuntu: Invalid Status in “unity-2d” source package in Natty: Triaged Bug description: This bug is similar to bug 1016386, which was recently fixed for thunderbird 13.0.1. When testing the latest Mozilla betas from the mozillateam/firefox-next and mozillateam/thunderbird-next PPAs, I noticed that firefox and thunderbird 14.0 have a similar problem. I believe this is specific to unity-2d in Natty. I cannot reproduce it in the default Natty fallback (Ubuntu Classic) when unity-2d is not installed. Thunderbird drop down menu test case: 1. Launch thunderbird from the Unity launcher 2. Edit -> Account Settings 3. Click on account actions, it should show a drop down of choices, but doesn't Firefox drop down menu test case: 1. Launch firefox from the Unity launcher 2. Edit -> Preferences 3. Click the "When Firefox starts" drop down. It should show several choice but doesn't. NOTE: Only after triggering the drop down menu bugs, will the following test cases fail. Firefox drag and drop test case: 1. Launch firefox from the Unity launcher 2. Enable the bookmarks toolbar: View -> Toolbars -> Bookmarks Toolbar 3. Now attempt to drag the globe from the left side of the URL box into the bookmarks toolbar area. It should add the URL as a bookmark and create an icon but doesn't. Firefox right click test case: 1. Launch firefox from the Unity launcher 2. Try right clicking (on a link or in a dead area). The right click menu doesn't display. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1020198/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp