1. Go to the end
2. Go back to normal world
3. Find destroyed item frames
4. Save and quit & reopen world
5. Items still on the ground and also on wall/chests etc.

Also good to mention. The game still 'knows' the item frames are there before relogging. Because you cannot place that item back on the spot where it was (or is, sort of). You'll 'lose' the item, but it won't be placed. When left clicking somewhere else you get the item back in hand again, (or it's placed depends if you can place a frame on the place you clicked).

Maybe good to mention this too: It's not all item frames , it's only some of them. (looks chunck related, first time it was the back part and not the front of the chests, second time the front and not the back). (I spawned in at the same spot both times when coming back from the end)

Below are some screenshots from before and after the save & quit and reopening world. 

PS: Some chests never had item frames. So every single one 'breaks' but is still there when reopening world.