I was experimenting with item frames in combination with redstone (item frame locks) and at the beginnig it worked out well, but after I did not touch the screen for a short time and then flipped the item in the item frame half of the world (either left or right: depends on where I stood in relation to the item frame) was invisible/ did not load.
-What I expected: normally working item frame lock (like before the bug appeared).
-What actually happened: half of the world turned invisible even after quitting to title and entering the world again and parts of the MCPE start screen were flickering or totally turquoise. After closing MCPE completely everything went back to normal.
-How to reproduce: I could not reproduce this bug until yet because I do not actually know what caused it I only remeber what I did just before the bug appeard.