I was playing in one of my world's when I opened a chest and noticed a change in background. I did it over again and found it my render distance would go to the lowest setting and when the UI was closed it went back to what it was originally.
Main issue: Render distance changes when a UI is opened
EXPECTED: The render distance should stay the same when UI are opened and closed.
Sorry about the photo quality. Hopefully you can see the change in render distance.
Edit: This effects all bedrock platforms/versions.