I found a wall clipping bug involving trapdoors activated by buttons. There should be a few screenshots attached for reference.

I noticed that when a player presses the button on the floor and walks into the activated trapdoor, the player would often clip through the wall. I used iron blocks for the wall, an oak trapdoor, and a wooden button in the screenshots, however; after a bit of experimentation, I found that really any combination of blocks, trapdoors, and buttons seem to work.