Bottom face of cauldron desyncs players flying in creative mode.

The bottom face of the cauldron causes desync to players flying under it in creative mode if the player has bumped their head on the bottom of the cauldron while flying.

Steps to reproduce

1. In creative mode, place a cauldron with enough space under it for a player to pass while flying.

2. Go under the cauldron and hold the jump button to go up until the player’s head bumps into the bottom of the cauldron.

3. Without using the jump or sneak keys or exiting fly mode, move away from the cauldron.

4. Without using the jump or sneak keys or exiting fly mode, fly back towards the cauldron.

Expected result

The player is able to pass under the cauldron freely, as their head was aligned to the bottom just fine.

Actual result

The player initially passes under freely, but is bounced back, as if the server disagrees on the player’s position. The player cannot pass under the cauldron. Attempting to fly under normal blocks in this state also results in desync.