Djun

I can confirm that bees have disappeared in my world as well. This happened even after enclosing the bee farm in a dome within one chunk. I have attached a screenshot of my bee farm with chunk borders on. I used to have a dozen+ bees but they disappeared after I traveled far away for too long.

I've checked the doors, including the one in the video, they are consistent with how they look to us. open=false when we see them as shut and open=true when we see them as open. Even the ones that are "placed the wrong way".