I have just upgraded to Saucy but am facing several issues. Any window that I open is unresponsive or only starts responding after a very long time to mouse clicks. I just cannot use my mouse or touchpad at all and am having to navigate entirely with my keyboard. Even that stops working occasionally. Currently I'm using the older kernel 3.8 to get around my Wifi issues but the issue was present even in the 3.11 kernel.
EDIT: I might add that the issue comes up gradually i.e. after I do a
sudo service lightdm restart or right after initial login, the windows seem to work fine but after some time they stop responding completely to mouse events and sometimes to key presses as well.
UPDATE: After a prolonged run without rebooting, I find that the computer is becoming unresponsive to key presses every 5-6 seconds and then resumes after another 5-6 seconds. Also, the screen locking seems to be delayed and happens after I return to work after leaving the machine idle for some time. Further, sometimes the title bar of a window does not respond to clicks while the window content does or vice versa (This is particularly the case with nautilus)
Another thing is that while I am using any browser, whether Chrome or Firefox, the window automatically navigates back periodically i.e. it behaves as if I had pressed the back button when I clearly have not done so. At times this becomes really frequent and annoying. For example, while I was typing this question, I kept getting popups telling me that I am in the middle of an edit and if I really wanted to navigate away from this page. I have tried clearing my browser cache and that has only made it a little less frequent. I don't know if this is some kind of virus that came free along with the Saucy upgrade or some kind of bug or configuration problem in my computer. Note that I am not being redirected to a particular site but am just being made to go back in my browser history. Having never faced such a problem on Ubuntu, I'm at my wit's end on what to do about it. Any help will be greatly appreciated.