Solution is here: http://superuser.com/questions/332782/middle-click-tab-opening-stopped-working-in-firefox/332794#332794
for me: I simply uninstalled GreaseMonkey -- 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/843680 Title: middlemouse.openNewWindow setting ignored Status in “firefox” package in Ubuntu: New Bug description: Since this morning's update (6.02), clicking on a link with the middle mouse button does not open the link in a new window, regardless of the contents of middlemouse.openNewWindow. The middle mouse button is working on the OS. Ubuntu release: Natty Package version: 6.0.2+build2+nobinonly-0ubuntu0.11.04.1 Expected: Clicking on a link with the middle mouse button opens it in a new window Happened: Nothing Extra info: all of middlemouse.openNewWindow, middlemouse.contentLoadURL, middlemouse.paste and middlemouse.scrollbarPosition are set to true Any extra information needed to catch this bug, lemme know. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/843680/+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
