Moved from MC-220390 to here.

The bug

If you get out of the water while sprint-swimming and collide with a ceiling and another adjacent block, you will take suffocation damage.

How to reproduce

1. Go to an ocean.
2. Create this L-shaped structure above water with solid blocks:

   A : air
   S : solid block
   W : water
   
   A S S A
   A S A A
   W W W W
   

1. In survival mode, start swimming (W + Ctrl).
2. Exit the water (holding W + Ctrl + Space) and collide with the inside corner of the structure.
      You will take unexpected damage.

Examples

• MC-234665 Damaged when exiting the water.mp4
• MC-234665 Bug with hitboxes on.mp4