If custom dimensions are added via datapack, the optimize world feature would fail saying that the dimensions are unknown dimension types.
[17:57:26] [Render thread/INFO]: Loaded 2 recipes
[17:57:26] [Render thread/INFO]: Loaded 2400 advancements
[17:57:30] [pool-7-thread-1/ERROR]: Error upgrading world
java.lang.RuntimeException: Unknown dimension type : ResourceKey[minecraft:dimension / battle:dig_small]
at net.minecraft.class_3360.method_14745(class_3360.java:279) ~[client-intermediary.jar:?]
at net.minecraft.class_3977.method_43411(class_3977.java:77) ~[client-intermediary.jar:?]
at net.minecraft.class_3977.method_17907(class_3977.java:51) ~[client-intermediary.jar:?]
at net.minecraft.class_1257.method_5404(class_1257.java:132) ~[client-intermediary.jar:?]
at java.lang.Thread.run(Thread.java:833) [?:?]
Comments 3
We do not have enough information to find the cause of this issue.
Please attach the crash report found in [minecraft/crash-reports/crash-<DATE>-client.txt|https://minecrafthopper.net/help/finding-minecraft-data-folder/] here.
If you cannot find a crash report, please attach the full launcher log found in [minecraft/launcher_log.txt|https://minecrafthopper.net/help/finding-minecraft-data-folder/].
This issue is being temporarily closed as Awaiting Response. Once the requested information has been delivered, the report will be reopened automatically.
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I have tried this with my own datapack that contains a custom dimension/dimension type and was unable to replicate the issue.