Sorry for bad quality, but basically when I want to stand under this little construction here, I have to crouch. Now when I try to stand up and 'play a bit around', I land on top of those blocks due to some glitch. Not sure if this is report worthy or maybe you already know it
Better quality:
Edit: I build an elevator based on this bug:
(R.I.P in PEACE soon, I guess :CCC)