0xAAZZ

Hello, I have to this error ``` 22-03-27 18:19:26 WARN LevelMetadata [455] - 'poi/r.-1.3.mca' is empty?! java.lang.UnsupportedOperationException at java.base/java.util.Collections$UnmodifiableCollection.retainAll(Collections.java:1083) at de.piegames.blockmap.world.RegionFolder$CachedRegionFolder$1.rendered(RegionFolder.java:508) at de.piegames.blockmap.world.RegionFolder$CachedRegionFolder$1.rendered(RegionFolder.java:505) at de.piegames.blockmap.world.ChunkMetadata$ChunkMetadataRendered.visit(ChunkMetadata.java:85) at de.piegames.blockmap.world.RegionFolder$CachedRegionFolder.lambda$filterStructures$1(RegionFolder.java:505) at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183) at...