Confirm on 13w33c through 1.8-pre1 Single Player, Mac OS X v10.9.4.
I had the 4th button on my mouse set to activate Mission Control, and when I accidentally clicked it, the game doesn't pause. If I click the left/right mouse button and the Mission Control button at the same time, the left/right mouse button is stuck, and I have to pause/unpause the game to fix it.
I think having the game to pause when Mission Control is activated would fix the problem.
Confirm in 14w34d, pickaxe and axe re-appear after broken. Not sure if it has anything to do with the Unbreaking enchantment though.
Confirm 14w34d, Launcher version 1.5.2 for WIndows.
Why is this marked as duplicate? MC-1519 is about toggling fullscreen and this is about Mission Control in Mac OS, they are totally different.