The Bug

When Endermen freeze in powdered snow, suffocate, take damage from rain/water, etc. in a vehicle, they attempt to teleport, resulting in teleportation particles and sounds of the Enderman teleporting without the Enderman teleporting.

How to Reproduce

This example is for suffocation. The others listed above are similar to reproduce.

1. Make a 2x2 roof two blocks from the ground out of solid blocks.
2. Place a boat near the roof. Summon an Enderman near it and push it into the boat.
3. Row the boat so that the Enderman's head is inside the block.
4. Get out of the boat.

Observed Results

The Enderman attempts to teleport out of the boat but fails continuously, resulting in an abnormally large amount of teleportation particles and sounds.

Expected Results

Endermen take damage in the boat but do not attempt to teleport.