After double-tapping "w" while in water/waterlogged scaffolding, the screen shakes violently, and a few seconds later, stops. I believe this is because the game thinks that it should be running, but also thinks it should be swimming, and therefore switches between the two quickly.

\\{{https://drive.google.com/file/d/1QcXPc4ObOyOa-RieGSW3AqjwDsCmNv_I/view?usp=sharing}}

 The link above is the video showing this happen.