Slabs can be placed in either the upper or lower section of a block. There's a relatively new feature that allows half blocks of water, but when you place water on top of a slab that is set to the top half of a block the water will be placed beneath the slab as a half block of water instead of being placed on top of the slab.
Linked issues
duplicates 1
Comments 1
Thank you for your report!
We're actually already tracking this issue in MC-131021, 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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