---- Minecraft Crash Report ----
// Why did you do that?

Time: 5/25/20, 12:28 AM
Description: Exception in server tick loop

java.lang.IllegalArgumentException: value already present: chf@d5af7f7
	at com.google.common.collect.HashBiMap.put(HashBiMap.java:287)
	at com.google.common.collect.HashBiMap.put(HashBiMap.java:262)
	at gg.a(SourceFile:51)
	at gg.a(SourceFile:62)
	at gl$a.a(SourceFile:28)
	at net.minecraft.server.MinecraftServer.a(SourceFile:407)
	at net.minecraft.server.MinecraftServer.i_(SourceFile:334)
	at enr.d(SourceFile:65)
	at net.minecraft.server.MinecraftServer.run(SourceFile:666)
	at java.base/java.lang.Thread.run(Thread.java:834)


A detailed walkthrough of the error, its code path and all known details is as follows:
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-- System Details --
Details:
	Minecraft Version: 20w21a
	Minecraft Version ID: 20w21a
	Operating System: Mac OS X (x86_64) version 10.15.4
	Java Version: 11.0.6, Oracle Corporation
	Java VM Version: OpenJDK 64-Bit Server VM (mixed mode, sharing), Oracle Corporation
	Memory: 3245255168 bytes (3094 MB) / 3974103040 bytes (3790 MB) up to 7516192768 bytes (7168 MB)
	CPUs: 4
	JVM Flags: 16 total; -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCIProduct -XX:-UnlockExperimentalVMOptions -XX:ThreadPriorityPolicy=1 -XX:+UseG1GC -XX:+UnlockExperimentalVMOptions -XX:MaxGCPauseMillis=100 -XX:+DisableExplicitGC -XX:TargetSurvivorRatio=90 -XX:G1NewSizePercent=50 -XX:G1MaxNewSizePercent=80 -XX:InitiatingHeapOccupancyPercent=10 -XX:G1MixedGCLiveThresholdPercent=50 -XX:+AlwaysPreTouch -Xms512m -Xmx7168m
	Player Count: 0 / 8; []
	Data Packs: vanilla
	Type: Integrated Server (map_client.txt)
	Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.