The bug
When adding cullface to the tops of bottoms of glass panes, the game crashes. It is yet to be discovered if this affects any other blocks.
How to reproduce
Create a resourcepack that tries to add cullface to the tops or bottoms of glass panes
Open the game
Place a glass pane, and then the game crashes.
Crash report
17w47a\: [^crash-2017-11-23_15.17.05-client.txt]
Description: Tesselating block model
java.lang.IllegalArgumentException: Cannot get property null as it does not exist in bal{block=minecraft:glass_pane, properties=[east, north, south, west]}
at bal$a.c(SourceFile:174)
at auw.c(SourceFile:65)
at bal$a.c(SourceFile:380)
at bzz.c(SourceFile:94)
at bzz.a(SourceFile:44)
at bzx.a(SourceFile:62)
at ccb.b(SourceFile:180)
at cbx.a(SourceFile:100)
at cbw.b(SourceFile:140)
at bzj.a(SourceFile:925)
at bzc.b(SourceFile:1158)
at bzc.a(SourceFile:1093)
at bzc.a(SourceFile:951)
at bmg.b(SourceFile:810)
at bmg.a(SourceFile:369)
at net.minecraft.client.main.Main.main(SourceFile:134)
Linked issues
Attachments
Comments

[media]
here ya go

forgot crash reports was a thing lol
Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response.
We do not have enough information to find the cause of this issue.
Please attach the crash report (.minecraft/crash-reports/crash-<DATE>-client.txt) here.
If no crash report was created, please attach the launcher log (.minecraft/launcher_log.txt) here.
Once attached, the report will be reopened automatically.
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