If you are fighting the ender dragon in the end dimension then save and exit the game and join back into your world, then the ender dragon will become frozen, and the portals will spawn. It's as if the fight ended and you can go back to the overworld, but a still, invincible dragon remains.
MCPE-34008
Ender Dragon Despawns
Resolved
Duplicate
0
Thank you for your report!
However, this issue is a Duplicate of MCPE-31765.
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