If a player creates a world and dies without setting a spawn point (Bed, Respawn Anchor, /spawnpoint), they will not have a valid spawn point and will respawn in a softlocked state where their camera appears inside their player model. They can no longer play the world. This only affects 20w13a, not 20w12a or before.
Thank you for your report!
We're actually already tracking this issue in MC-175988, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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