Players cannot sleep underwater because the bed was "obstructed" where it obviously isn't since there aren't any solid blocks that could actually obstruct the bed.
Steps to Reproduce
Place a bed underwater.
Make sure there aren't any blocks that could've obstruct the bed.
Have either water breathing or conduit power.
Wait for nightfall.
Attempt to sleep.
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We're tracking this issue in MCPE-87848, so this ticket is being resolved and linked as a duplicate.
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