I have only witnessed it occurring on the realm.
I found that due to personal testing the leaves and other floating blocks reappear upon the chunk unloading and reloading REALMS-9667 my own article mentions this effect happening. so it has something to do with the Realm and Chunk loading/saving perhaps? or some kind of old terrain code meets new terrain coding issue?
Ok, thanks! Had no clue it was a duplicate, sorry!
Honestly, this happening is one of the most annoying things ever.
Happens in 1.7.2
Can confirm.
Additionally, it seems to be only happening when on the realm with someone else and the chunks are unloaded and then reloaded