In a recent snapshot, they made it to where your player height changes as your environment does. (example, if you push a block onto your head) However, this affects your swimming mechanics as the two mechanics will battle each other and it messes up your swimming. (the best way to recreate this is trying to swim around a shipwreck)
Linked issues
is duplicated by 3
Comments 8
Relates to MC-148627
This problem has disabled the ability to move into one block spaces under certain conditions, making actions that were simple in 1.13.2 extremely complex and glitchy to perform. Like I said in MC-148627, this glitch should be fixed ASAP because it could kill players swimming around in coral, icebergs, caves, ocean monuments, ruins, and especially shipwrecks. I really hope they fix this or I will rarely play 1.14, as trying to explore the ocean is annoying and unnecessarily deadly thanks to this glitch and also water flow glitches such as MC-144929. We seriously have enough swimming glitches in 1.13.2 (with the most notorious one being MC-133414!).
Unfortunately 1.14 was fully released without this being fixed.
Me and a friend we're actually playing on a server and she DID actually die bc of this. This is a critical bug and I'm a little disappointed in Mojang for not fixing this bug before 1.14 was fully released.
The only scenario where I was able to reproduce this is by sneaking. Flying with elytra or "crawling" (by pushing a block inside of your head) seem to be unaffected.
Can confirm. The problem here seems to be that you can't swim while you are in a space that forces you to sneak.