I am using Linux (CentOS, Gnome 3.8.4) and I suspect this is an OS dependent problem.
When I input some text, and use mouse to select the text as follows: First press the mouse left button, keep holding the button while move the mouse to select something, and do not release the button for about 5 seconds (i.e. typical selection process, only hold the button for longer time). Then a window jumps out:
I have to press
wait (if I press
Esc, Mathematica is killed, without asking me to save anything).
I am not sure if it is a bug of Mathematica, or the Linux Gnome side. When using KDE there is no such problem.
(1) Sounds like my expression is not clear :) Here is screencast:
Note that after selecting the letter a, I didn't release the mouse button.
(2) In Mathematica 9, there is no such problem.