I found the cause of the problem in my case. As part of the Maverick to Natty to Oneiric upgrade, something installed the xbindkeys package (xbindkeys-1.8.5-1). The file ~/.xbindkeysrc has definitions including:
"xterm" c:41 + m:0x4 This unfortunately defines a Ctrl-f shortcut which has global scope (i.e. cuts across all applications) that starts an xterm. I uninstalled xbindkeys, and of course its global Ctrl-f shortcut is now gone, thus enabling all of the application-specific Ctrl-f shortcuts, such as Ctrl-f for opening the search box in firefox, to work again. I'm not sure why xbindkeys was installed during the Maverick-Natty- Oneiric upgrade. Anyway, I hope this bug report will help others who may encounter the same issue. @Karl Ostmo, is xbindkeys installed on your system? ** No longer affects: unity-2d ** No longer affects: unity ** Changed in: unity (Ubuntu) Status: Incomplete => Invalid ** No longer affects: lightdm ** No longer affects: firefox ** No longer affects: gnome-session -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/880517 Title: CTRL+f shortcut does not work in any application after Oneiric upgrade To manage notifications about this bug go to: https://bugs.launchpad.net/xorg-server/+bug/880517/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp