When using the command "/execute in minecraft:overworld run tp [player] ~ ~ ~" to exit the End while the ender dragon is still alive, the "Ender Dragon" health bar displays for a split second after teleporting to the Overworld on most occasions. The same occurs if using the command to teleport directly to the Nether ("/execute in minecraft:nether run tp [player] ~ ~ ~"). The health bar does not display in the loading screen. Although the bug affects both specified versions, it appears to occur with much more consistency in 1.21 Pre-Release 3 than in 1.20.6.

It also affects 1.21 Pre-Release versions 1, 2, and 4, where the health bar seems to appear for fractionally longer in the Overworld/Nether in both versions.

Steps to Reproduce:
1. Place yourself in the End via a method of your choice, whether it be via portal or the "/execute" command.

2. Use the command "/execute in minecraft:overworld run tp [player] ~ ~ ~" to teleport yourself back to the Overworld while the ender dragon is still alive.

3. Observe that the ender dragon's health bar may reappear in the overworld for a split second after the loading screen has disappeared. Note that it is not visible in the loading screen itself.

It may take multiple attempts to observe this bug as it does not occur 100% of the time. In order to reproduce for the Nether, simply replace "overworld" with "nether" in the specified command in step 2.