NeilPeel

Screenshot .42 is morning.. the bed is diagonally through the corner where the villager is standing..
I can walk through the wood posts but the villager just stands there..
Screenshot .13 is the same day (nighttime); yep, villager still there.

.00 is the next morning.. The other villager seems to have escaped, this time, though I'd say he spawned outside the wooden posts when waking up.. I noticed two villagers stuck inside the same posts previously..

In addition.. Villagers think they can enter a bed through a diagonal (where two walls meet) and sometimes do this. When these wooden columns are placed around the corner block, the villagers act downright weird.. They think they're blocked from getting between the two posts and want to get to the bed through the diagonal - but they can't get in and so just stand outside, beside the post.
If you chop the posts down, they then go straight to their bed - through the diagonal block..

Same here.. Travelling along on your horse, dismount and it sometimes disappears..
If you walk about 100(ish) blocks away and come back again, the horse reappears..

1.14.2 with Optifine (not sure without).

Same issue here (with gravel). Glitched out of the world and all items disappear.

I've also got exactly the same problem - but with Pumpkins (you read that right)..

I was using bonemeal on the plant and it must have grown into a pumpkin right where I was standing (as soon as the stem had grown).

I was killed and all my gear disappeared - I went back (pretty quickly) to check..