So this has now happened about 3 times in the past year, but it's incredibly frustrating. I should also mention I'm on a fairly new Imac, running InDesign CC2015. When selecting print booklet the dialogue disappears, and I am taken back to my document. I can change my tools on the left, though they are not usable, as any attempt to use them on the document does nothing.
When trying to select any of the menu's on my top bar, most everything is grayed out, except for recent documents, as that's an arrow menu. When hovering over that It shows the recent documents, but I cannot select any, as all of them are grayed out. This graying out is true across all of the menus. I am not able to save my work unless I exit out of the document itself, then it asks me to save before I leave.
I am also able to delete pages for some reason, but not undo. It's almost like I have a dialogue active, but I can still switch between open files back and forth.
In the end I am required to force quit from the force quit menu, otherwise my InDesign is absolutely useless when this happens. Is this possibly a product of my print drivers not agreeing with InDesigns dialogues? As I said this has happened all of 3 times, but all 3 times it's been pretty terrible. Any help would be appreciated. If I can, next time it happens I will try to take some video.