I experienced an issue occurring the end cities on multiple occasions. When a shulker shoots it's attack and hits me with it, I float up because of its effect. When I float up because of the effect my head will glitch into the block causing drowning damage, or will cause no damage and allow me to see through the world. Roughly, I'd say it happens about %50 of the time, the doesn't seem to be a particular variety of purpur block causing the issue. It's a fairly minor issue, but it can be fairly annoying when spending extended periods of time in the end. Hope to hear back, thank you very much for the help.