I died in my Hardcore world, and went to delete it since I couldn't respawn. However, when the Delete World menu was in front of me, the background had changed into the screen of my death. I tried deleting other worlds (as a test) and they too had their backgrounds altered.
I also tried editing a world, and, once again, the background was different.
Attached are three pictures, two being me attempting to (test) delete two different worlds after I died in my hardcore world, and one when I tried editing a world after I died. In all of them, the background is the scene from when I died in my hardcore world.