7 years on - still ****ed !
I gave up with Ubuntu after a niggling bug crept in around 8.04 which was confirmed by a few other users. Basically *something* choked the mouseclicks. You could see the mouse., Hovering over buttons triggered a mouse_over event, but clicking went nowhere.
Initially it looked like a wireless problem. But a few other users confirmed the same issue with wired mice.
Bugs were raised, posts made, and I was amused (but not surprised) to get an email recently from an Ubuntu forum because a desperate user had resurrected a post of mine asking if I ever found a solution. Not sure if they agree with my solution, which was to dump Ubuntu. (Debian has been 100% rock solid).
What did amuse me was digging into the bug reports, it seems that every so often someone closes the bug report with the reason "this is over a year old, so must have been fixed".
I am not, nor do I wish to be a linux developer. My contribution to the effort was to detail the bug as accurately as possible, along with my observations. I got as far as restarting the X-Server "fixed" it (for a while) along with a suspicion that something in the tray was popping up, stealing mouse focus, and never returning it.
Given this bug effectively rendered a remote installation unusable (which is how I found it) it's hardly trivial. It happened in GNOME, XFCE and KDE, so is quite primitive.
I don't expect to hear how this is the year of the Linux desktop anytime soon.
Notice the bug has never been "fixed". And that 2015-2006 = *9* years.