Your terminal output looks like bug #145059, but I don't know if that's causing the slowness.
** Changed in: gnome-control-center (Ubuntu) Sourcepackagename: None => gnome-control-center -- gnome-appearance-properties is very slow and its GUI does not refresh https://bugs.launchpad.net/bugs/147040 You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is a bug contact for gnome-control-center in ubuntu. -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
