In the snapshot 19w03c (recent) the map in a itemframe disappeared after defeating the ender dragon. Another bug, you can't enter the end gateway also after the defeat of the ender dragon

Put the summary of the bug you're having here

What I expected to happen was...:
while defeating the ender dragon it must have put stress on chunk loader for it not to work

What actually happened was...:
n/a

Steps to Reproduce:
1. Log off and back on the world then it should be good