Actually, destroying the End Crystal used to respawn the Ender Dragon will cause the portal to reappear. However, destroying it with explosives, such as beds, TNT, etc., will destroy the portal when it explodes.
How to reproduce the issue:
Respawn Ender Dragon.
Destroy the End Crystal with an explosion upon respawning.
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We are tracking this issue in MC-259670, so this ticket is being resolved and linked as a duplicate.
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