Item frame contains invisible Clock - Ender Chest has invisible compass

Seed: Coastal Village (-1813740965); Survival Mode; Normal Difficulty; Infinite Size; world created after Beta v 1.5.0.

I had an Item Frame which contained a Clock. The Clock was located on an oak block next to a door. It has been there through many different MCPE Builds. When I loaded the world today, I noticed the Item Frame looked empty. When I hit the empty Item Frame with a diamond axe, the clock popped-out and floated above the floor. The invisible clock had magically reappeared. I think this is a similar issue which effected beds in previous MCPE Beta builds. The bed appeared to have disappeared, but when you struck the area where the bed was placed, it would reappear.

I opened my Ender Chest and the compass I placed there was gone. I moved my mouse to each slot and found a slot which was labeled compass. I dragged the invisible compass to a slot in my inventory, see attached screenshot. Finally, I dragged the invisible compass to my Hot Bar, and it magically re-appeared. I wonder if this has to do with chunks loading?