The part of the end sky is black on short distance

It happened a few months ago, when I went to the end on short distance, the part of the end sky was black.
I will prove it with the screenshots I took.
Here's how to confirm a bug:
1. Go to the end.
2. Pause the game and click on options, video settings
3. Set render distance to 4 or something.
4. Unpause the game and confirm the bug that I found.