pretty much if a walls underwater it becomes a stump wall, if you don't know what i mean try placing a wall connected to two blocks above water than try it underwater, you will see that the wall has a little stump which is meant to only happen when a block is above it
MC-161018
Walls underwater turn into stumped walls
Resolved
Duplicate
1
Thank you for your report!
We're actually already tracking this issue in MC-138402, 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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