This is after the 2015.5 update.
If I Escape key out of a Make Text action with dialog on without using the actual stop action button, photoshop will cease to receive input, locking me in the text dialog. The program itself isn't locked up, everything shows the click animation but does nothing. The action is stuck in Play and the only thing I can do is force quit the entire thing, losing whatever unsaved work I had.
Escape key worked fine to cancel out of an action before the 2015.5 update.