I can't do any further testing because I am not running Kubuntu anymore, but I can explain what happened as a series of steps:
1. Set the screensaver to start in a minute. 2. Do not touch keyboard or mouse for a minute 3. Screensaver activates. That's good. But 1. Set the screensaver to start in a minute. 2. Move the mouse wheel but nothing else than the mouse wheel (the keyboard is not touched at all and the mouse is never moved, the only activity is the mouse wheel). For example, when reading a book or a long web site. 3. Screensaver activates. That's not good. I don't think the screensaver should activate while there's user activity, even if it is only the mouse wheel. Is that more clear ? Thank you. -- Mouse wheel doesn't prevent screen saver https://launchpad.net/bugs/39913 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs