The End dimension doesn't spawn the end dragon.
I tried to use an old world's end dimension, but the killing the dragon didn't activate the fountain or anything else that it is supposed to do. It just died.
The bossbar also didn't apear
MC-142098
End not working
Resolved
Duplicate
0
Lordeleren
(Unassigned)
Unconfirmed
Minecraft 19w02a
Retrieved
Thanks for the report; however this was already reported as MC-137467 (which also contains a few workarounds).