This happens for me as well. The issue shows up in Nautilus, Synaptic, Transmission, gedit, document viewer, and I'm sure more than a few other applications. It doesn't happen in gnome-terminal, chrome, firefox, clementine.
I can't find the package in synaptic to downgrade it to (I'm looking for gtk+3.0 correct?), so I cannot test the PPA just yet. Any suggestions? I am however using the scrollwheel to switch workspaces. Turning this off does allow me to scroll within the above applications, but I need to be focused on that application. If it's a background app, I still cannot scroll. This functionality in applications where it previously worked, did not change, -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/1171342 Title: mouse scroll wheel not working in gedit & System Monitor Status in GTK+ GUI Toolkit: Fix Released Status in X.Org X server: Confirmed Status in “gtk+3.0” package in Ubuntu: Fix Released Status in “xorg-server” package in Ubuntu: Triaged Bug description: Open System Monitor Using mouse wheel button - scroll up or down - list does not move. If Press the wheel button and then scroll up or down the list will move. This also occurs in Gedit. Firefox and Terminal work as expected. IE do not need to press the wheel and then scroll Linux kylea-hpxt 3.8.0-19-generic #29-Ubuntu SMP Wed Apr 17 18:16:28 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux Description: Ubuntu 13.04 Release: 13.04 To manage notifications about this bug go to: https://bugs.launchpad.net/gtk/+bug/1171342/+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