Workaround
Open your world’s level.dat in an NBT editor such as this one, delete Data > Player > active_effects, save the file, replace your old level.dat with the edited one and load the world again.
Attempting to load a world in which you have a potion effect fails with an “Invalid player data” error message.
This can be reproduced while riding a nautilus or giving yourself the effect using /effect and saving and leaving the world, then proceeding to play the world where you gave yourself the effect.
Expected result
The world loads as normal.
Actual result
The world fails to load, displaying a server join attempt fail message, saying “Connection Lost, Invalid player data“.
Linked issues
is duplicated by 36
MC-302710
Loading a world that you are riding a nautilus in causes you to be disconnected with the "invalid player data" message.
Resolved
MC-302706
Closing World While Riding Nautilus Causes Invalid Player Data Error on Relaunch
Resolved
MC-302747
Turtle Helmet when equipped causes corrupt player data
Resolved
MC-302738
Logging out with a status effect causes invalid player data
Resolved
MC-302730
Leaving and rejoining a world with a potion effect causes invalid player data
Resolved
Attachments
Comments 6
Duplicate of MC-302730
Noticed this as well because my turtle helmet trapped me in a never ending state of having a potion effect.
seems to be all potion effects - not just breath of the nautilus
i have several worlds i can’t open because the data pack gives saturation immediately
using nbtexplorer to remove the active_effects field lets me open the world again