Whenever another wall is stacked on top of a previous layer is caused the bottom layer to get joints where it should be smooth. This bug has been around for as long as I can remember and I would love for it to be fixed because it would aid in builds and actually be correct.
Please attach the crash report (
[minecraft|http://hopper.minecraft.net/help/finding-minecraft-data-folder]/crash-reports/crash-<DATE>-client.txt
), otherwise we can not diagnose this issue.For technical support please use the Mojang Support Center.
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