The Bug:
When I try to teleport below level 0 from the overworld to another dimension, it freezes on the "Loading terrain..." screen.
It resets if the player dies (in survival or creative because it falls into the void).

What I expected to happen was...:
the "Loading terrain..." screen would go away after a few seconds.

What actually happened was...:
the "Loading terrain..." screen never goes away, unless the player dies.

Steps to Reproduce: MC-248189.mp4

• Go to spectator mode.

  /gamemode spectator

• Teleport below level 0 to the Nether or The End:

  /execute in minecraft:the_nether run tp @s ~ -1 ~
  /execute in minecraft:the_end run tp @s ~ -1 ~

    You will notice that the "Loading terrain..." screen never goes away.