Right after 3.6.7 download, clicking on Firefox shortcut produced (1) unending stream of windows asking if I wanted to remove the shortcut. Clicking them away only led to still more, one behind the other in the center of the screen. This then happened with every other clicked shortcut icon. (2) Clicking to open an e-mail in Thunderbird then led it to chew through and delete all further e-mail, stopped only by closing Thunderbird. Rebooting did no good. Only a system restore.