Setting spawn point in End leads to extreme lag and inability to break blocks.

Description:

When using the /spawnpoint command to set a spawn point in the End, if you defeat the Ender Dragon for the first time and then attempt to return to the Overworld via the End Portal, the game will return to the End after the End Poem finishes. At this point, the world becomes extremely laggy, and you cannot break or place any blocks.

When you re-enter the world (or reload the save), the lag issue resolves, but you are teleported to a faraway location instead of the spawn point set in the End.

Expected Behavior:

When returning to the Overworld via the End Portal or during any teleportation process, the player should be correctly teleported to the current spawn point.