The game crashed whilst exploring the world, vanilla 1.18 pre-release 4 I've attached the crash log and full game log. ---- Minecraft Crash Report ---- // There are four lights! Time: 19/11/2021, 14:22 Description: Exception in server tick loop java.util.concurrent.CompletionException: net.minecraft.ReportedException: Accessing PalettedContainer from multiple threads   at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:315)   at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:320)   at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1159)   at java.base/java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:482)   at net.minecraft.server.level.ChunkTaskPriorityQueueSorter.void lambda$message$1(java.lang.Runnable,net.minecraft.util.thread.ProcessorHandle)(ChunkTaskPriorityQueueSorter.java:58)   at net.minecraft.util.thread.ProcessorMailbox.boolean pollTask()(ProcessorMailbox.java:91)   at net.minecraft.util.thread.ProcessorMailbox.int pollUntil(it.unimi.dsi.fastutil.ints.Int2BooleanFunction)(ProcessorMailbox.java:146)   at net.minecraft.util.thread.ProcessorMailbox.void run()(ProcessorMailbox.java:102)   at java.base/java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1395)   at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)   at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)   at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)   at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)   at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165) Caused by: net.minecraft.ReportedException: Accessing PalettedContainer from multiple threads   at net.minecraft.server.level.ChunkMap.java.util.concurrent.CompletableFuture lambda$scheduleChunkGeneration$20(net.minecraft.world.level.ChunkPos,net.minecraft.server.level.ChunkHolder,net.minecraft.world.level.chunk.ChunkStatus,java.util.concurrent.Executor,java.util.List)(ChunkMap.java:639)   at com.mojang.datafixers.util.Either$Left.null map(null)(Either.java:38)   at net.minecraft.server.level.ChunkMap.java.util.concurrent.CompletionStage lambda$scheduleChunkGeneration$22(net.minecraft.world.level.ChunkPos,net.minecraft.server.level.ChunkHolder,net.minecraft.world.level.chunk.ChunkStatus,java.util.concurrent.Executor,com.mojang.datafixers.util.Either)(ChunkMap.java:621)   at java.base/java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:1150)   ... 11 more Caused by: java.lang.IllegalStateException   at net.minecraft.util.ThreadingDetector.net.minecraft.ReportedException makeThreadingException(java.lang.String,net.minecraft.util.DebugBuffer)(ThreadingDetector.java:27)   at net.minecraft.util.ThreadingDetector.void checkAndLock(java.util.concurrent.Semaphore,net.minecraft.util.DebugBuffer,java.lang.String)(ThreadingDetector.java:19)   at net.minecraft.world.level.chunk.PalettedContainer.void acquire()(PalettedContainer.java:55)   at net.minecraft.world.level.chunk.LevelChunkSection.void acquire()(LevelChunkSection.java:58)   at net.minecraft.world.level.chunk.BulkSectionAccess.net.minecraft.world.level.chunk.LevelChunkSection getSection(net.minecraft.core.BlockPos)(BulkSectionAccess.java:35)   at net.minecraft.world.level.chunk.BulkSectionAccess.net.minecraft.world.level.chunk.LevelChunkSection lambda$getSection$0(net.minecraft.core.BlockPos,int,long)(BulkSectionAccess.java:35)   at it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap.null computeIfAbsent(null)(Long2ObjectOpenHashMap.java:499)   at net.minecraft.world.level.chunk.BulkSectionAccess.net.minecraft.world.level.chunk.LevelChunkSection getSection(net.minecraft.core.BlockPos)(BulkSectionAccess.java:32)   at net.minecraft.world.level.levelgen.feature.OreFeature.boolean doPlace(net.minecraft.world.level.WorldGenLevel,java.util.Random,net.minecraft.world.level.levelgen.feature.configurations.OreConfiguration,double,double,double,double,double,double,int,int,int,int,int)(OreFeature.java:150)   at net.minecraft.world.level.levelgen.feature.OreFeature.boolean place(net.minecraft.world.level.levelgen.feature.FeaturePlaceContext)(OreFeature.java:52)   at net.minecraft.world.level.levelgen.feature.ConfiguredFeature.boolean place(net.minecraft.world.level.WorldGenLevel,net.minecraft.world.level.chunk.ChunkGenerator,java.util.Random,net.minecraft.core.BlockPos)(ConfiguredFeature.java:80)   at net.minecraft.world.level.levelgen.placement.PlacedFeature.boolean placeWithContext(net.minecraft.world.level.levelgen.placement.PlacementContext,java.util.Random,net.minecraft.core.BlockPos)(PlacedFeature.java:56)   at net.minecraft.world.level.levelgen.placement.PlacedFeature.void lambda$placeWithContext$4(net.minecraft.world.level.levelgen.feature.ConfiguredFeature,net.minecraft.world.level.levelgen.placement.PlacementContext,java.util.Random,org.apache.commons.lang3.mutable.MutableBoolean,net.minecraft.core.BlockPos)(PlacedFeature.java:56)   at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)   at java.base/java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:411)   at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)   at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)   at java.base/java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:411)   at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)   at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)   at java.base/java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:411)   at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762)   at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)   at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)   at java.base/java.util.stream.IntPipeline$1$1.accept(IntPipeline.java:180)   at java.base/java.util.stream.Streams$RangeIntSpliterator.forEachRemaining(Streams.java:104)   at java.base/java.util.Spliterator$OfInt.forEachRemaining(Spliterator.java:711)   at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)   at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)   at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)   at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)   at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)   at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)   at java.base/java.util.stream.ReferencePipeline$7$1.accept(ReferencePipeline.java:276)   at java.base/java.util.stream.Streams$StreamBuilderImpl.forEachRemaining(Streams.java:411)   at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)   at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)   at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)   at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)   at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)   at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)   at net.minecraft.world.level.levelgen.placement.PlacedFeature.boolean placeWithContext(net.minecraft.world.level.levelgen.placement.PlacementContext,java.util.Random,net.minecraft.core.BlockPos)(PlacedFeature.java:55)   at net.minecraft.world.level.levelgen.placement.PlacedFeature.boolean placeWithBiomeCheck(net.minecraft.world.level.WorldGenLevel,net.minecraft.world.level.chunk.ChunkGenerator,java.util.Random,net.minecraft.core.BlockPos)(PlacedFeature.java:44)   at net.minecraft.world.level.chunk.ChunkGenerator.com.mojang.serialization.Codec codec()(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.net.minecraft.world.level.chunk.ChunkGenerator withSeed(long)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.void applyCarvers(net.minecraft.server.level.WorldGenRegion,long,net.minecraft.world.level.biome.BiomeManager,net.minecraft.world.level.StructureFeatureManager,net.minecraft.world.level.chunk.ChunkAccess,net.minecraft.world.level.levelgen.GenerationStep$Carving)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.void applyBiomeDecoration(net.minecraft.world.level.WorldGenLevel,net.minecraft.world.level.chunk.ChunkAccess,net.minecraft.world.level.StructureFeatureManager)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.void buildSurface(net.minecraft.server.level.WorldGenRegion,net.minecraft.world.level.StructureFeatureManager,net.minecraft.world.level.chunk.ChunkAccess)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.void spawnOriginalMobs(net.minecraft.server.level.WorldGenRegion)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.java.util.concurrent.CompletableFuture fillFromNoise(java.util.concurrent.Executor,net.minecraft.world.level.levelgen.blending.Blender,net.minecraft.world.level.StructureFeatureManager,net.minecraft.world.level.chunk.ChunkAccess)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.int getBaseHeight(int,int,net.minecraft.world.level.levelgen.Heightmap$Types,net.minecraft.world.level.LevelHeightAccessor)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkGenerator.net.minecraft.world.level.NoiseColumn getBaseColumn(int,int,net.minecraft.world.level.LevelHeightAccessor)(ChunkGenerator.java:310)   at net.minecraft.world.level.chunk.ChunkStatus.java.util.concurrent.CompletableFuture lambda$static$12(net.minecraft.world.level.chunk.ChunkStatus,java.util.concurrent.Executor,net.minecraft.server.level.ServerLevel,net.minecraft.world.level.chunk.ChunkGenerator,net.minecraft.world.level.levelgen.structure.templatesystem.StructureManager,net.minecraft.server.level.ThreadedLevelLightEngine,java.util.function.Function,java.util.List,net.minecraft.world.level.chunk.ChunkAccess,boolean)(ChunkStatus.java:146)   at net.minecraft.world.level.chunk.ChunkStatus.java.util.concurrent.CompletableFuture generate(java.util.concurrent.Executor,net.minecraft.server.level.ServerLevel,net.minecraft.world.level.chunk.ChunkGenerator,net.minecraft.world.level.levelgen.structure.templatesystem.StructureManager,net.minecraft.server.level.ThreadedLevelLightEngine,java.util.function.Function,java.util.List,boolean)(ChunkStatus.java:289)   at net.minecraft.server.level.ChunkMap.java.util.concurrent.CompletableFuture lambda$scheduleChunkGeneration$20(net.minecraft.world.level.ChunkPos,net.minecraft.server.level.ChunkHolder,net.minecraft.world.level.chunk.ChunkStatus,java.util.concurrent.Executor,java.util.List)(ChunkMap.java:627)   ... 14 more A detailed walkthrough of the error, its code path and all known details is as follows: --------------------------------------------------------------------------------------- -- System Details -- Details:   Minecraft Version: 1.18 Pre-release 4   Minecraft Version ID: 1.18-pre4   Operating System: Windows 10 (amd64) version 10.0   Java Version: 17.0.1, Microsoft   Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Microsoft   Memory: 1615789512 bytes (1540 MiB) / 4932501504 bytes (4704 MiB) up to 6442450944 bytes (6144 MiB)   CPUs: 12   Processor Vendor: GenuineIntel   Processor Name: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz   Identifier: Intel64 Family 6 Model 158 Stepping 10   Microarchitecture: Coffee Lake   Frequency (GHz): 3.70   Number of physical packages: 1   Number of physical CPUs: 6   Number of logical CPUs: 12   Graphics card #0 name: NVIDIA GeForce RTX 3080   Graphics card #0 vendor: NVIDIA (0x10de)   Graphics card #0 VRAM (MB): 4095.00   Graphics card #0 deviceId: 0x2216   Graphics card #0 versionInfo: DriverVersion=30.0.14.7196   Memory slot #0 capacity (MB): 16384.00   Memory slot #0 clockSpeed (GHz): 2.67   Memory slot #0 type: DDR4   Memory slot #1 capacity (MB): 16384.00   Memory slot #1 clockSpeed (GHz): 2.67   Memory slot #1 type: DDR4   Virtual memory max (MB): 49080.70   Virtual memory used (MB): 37582.27   Swap memory total (MB): 16384.00   Swap memory used (MB): 217.65   JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx6G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M   Player Count: 1 / 8; [adj['abfielder'/31870, l='ServerLevel[-5596631996663293324]', x=-137.83, y=165.79, z=48.22]]   Data Packs: vanilla   Type: Integrated Server (map_client.txt)   Is Modded: Probably not. Client jar signature and brand is untouched; Server jar signature and brand is untouched