Jungle leaves disappear and placing blocks on leaves is broken

When building on jungle trees, leaves start disappearing, eventhough the tree trunk is still there. I've already seen this bug on earlier versions, but I now noticed it once more. Is this a feature or just a bug? Because I can't find anything about it on the internet, not even people talking about it being a bug. It is really annoying though, so I will classify it as a bug.

Oh, and also: Placing blocks on leaves is kinda broken. You click, the block is there for a millisecond and then it disappears again. Kind of annoying as well