Sledgehammer solution: resetting Firefox (https://support.mozilla.org /en-US/kb/reset-firefox-easily-fix-most-problems) fixed this issue for me.
-- 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/1294683 Title: Firefox menu button displayed Status in “firefox” package in Ubuntu: Confirmed Bug description: Since last upgrade to firefox 28 the firefox menu button on top left of the window is displayed. So we got two menus : the global menu (provided by unity) and the one provided by the menu button. Here is a screenshot : http://minus.com/i/brsaZiFVJE45f And here is my apt history log for the firefox update : Upgrade: firefox-locale-en:amd64 (27.0.1+build1-0ubuntu0.13.10.1, 28.0+build2-0ubuntu0.13.10.1), firefox-locale-fr:amd64 (27.0.1+build1-0ubuntu0.13.10.1, 28.0+build2-0ubuntu0.13.10.1), firefox:amd64 (27.0.1+build1-0ubuntu0.13.10.1, 28.0+build2-0ubuntu0.13.10.1), firefox-globalmenu:amd64 (27.0.1+build1-0ubuntu0.13.10.1, 28.0+build2-0ubuntu0.13.10.1) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1294683/+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