Whenever using the Nether Portal when near entities (Villagers, Armor Stands, Animals) The map unloads while still allowing the entities to move. This causes Armor stands to fall through the ground and allows villagers to move into walls, Upon entering the area again Villagers and Animals can suffocate in walls and armor stands simply continue to fall further and further.

Steps to Reproduce:

  [Step 1] Go to the Nether (possibly overworld also) place entities near the portal (Armor stands are most noticeable) Multiple Villagers near walls also works
  [Step 2] Go through the Nether portal
  [Step 3] Go back through the Nether portal

Observed Results:

Armor Stands falling through the ground, Villagers stuck in walls.

Expected Results:

Everything should be where I left it

Screenshots/Videos:

Attached below.

Notes:

Bug started to occur with the most recent update to 1.12.30