When you are hit while you're typing, the black screen (chat screen) disappears but the keyboard stay. You can't do chat or quit the game. To get rid of it you have to reset your device.
What I expected to happen was the black screen and the keyboard to stay when I was hit, and it would let me get out of the chat menu when I pleased. But the black screen disappeared, and the keyboard stayed.
What actually happened was I was just typing, when I was hit the black screen disappeared and the keyboard stayed. This has happened to me twice, both exactly the same way.
Steps to Reproduce:
1. Open the chat screen.
2. Press the chat button and start typing.
3. If your in survival, have someone hit you.
4. If you did what I typed up there, the black screen behind the keyboard disappeared and the keyboard stayed.