Same here, and any attempt at compiling brought up the "Compiling sketch..." box but nothing actually happened.
I tried a few of the suggestions on this thread. Opening another IDE instance (by opening a different sketch) seemed to work once, but then the problem came back.
It seems to me that there may be some sort of signal race, so it'll happen apparently randomly.
I've reverted to 2.3.2 (thanks @Arctic_Eddie for the link).