The bottom part of the Glass Panes is z-fighting with the top part of the cobblestone half slabs placed as a top half slab, as shown in the picture (far right) below. That picture is depicting the slabs are top half slabs, by comparing the positions with a regular block, being depicted while it is being punched. The cracking has nothing to do with the glass pane z-fighting issue.
How to reproduce:
Put a half-slab down, making it a top half slab.
Put a glass pane on top of it.
Notice the bottom of the glass pane z-fights with the top half slab.
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duplicates MC-220
And I thought people haven't reported this yet. Looks like the search terms "glass panes" didn't help me much.
Duplicate of: MC-220 - Please use the search function to see if your bug has already been submitted.
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