[17:20:39] [Server thread/INFO]: Starting minecraft server version 1.13.2-pre1
[17:20:39] [Server thread/INFO]: Loading properties
[17:20:39] [Server thread/INFO]: Default game type: SURVIVAL
[17:20:39] [Server thread/INFO]: Generating keypair
[17:20:39] [Server thread/INFO]: Starting Minecraft server on *:25565
[17:20:39] [Server thread/INFO]: Using default channel type
[17:20:41] [Server thread/INFO]: Preparing level "world"
[17:20:45] [Server thread/INFO]: Forcing world upgrade!
[17:20:45] [Server thread/INFO]: Counting chunks...
[17:20:46] [Server thread/INFO]: Upgrading all chunks...
[17:20:46] [Server thread/INFO]: 7% completed (44 / 626 chunks)...
[17:20:47] [Server thread/INFO]: 17% completed (112 / 626 chunks)...
[17:20:48] [Server thread/INFO]: 21% completed (134 / 626 chunks)...
[17:20:49] [Server thread/INFO]: 37% completed (235 / 626 chunks)...
[17:20:50] [Server thread/INFO]: 46% completed (289 / 626 chunks)...
[17:20:51] [Server thread/INFO]: 55% completed (348 / 626 chunks)...
[17:20:52] [Server thread/INFO]: 59% completed (370 / 626 chunks)...
[17:20:53] [Server thread/INFO]: 63% completed (396 / 626 chunks)...
[17:20:54] [Server thread/INFO]: 83% completed (521 / 626 chunks)...
[17:20:55] [Server thread/INFO]: 92% completed (579 / 626 chunks)...
[17:20:55] [pool-4-thread-1/INFO]: World optimizaton finished after 10411 ms
[17:20:55] [pool-4-thread-1/INFO]: ThreadedAnvilChunkStorage (DIM-1): All chunks
 are saved
[17:20:55] [pool-4-thread-1/INFO]: ThreadedAnvilChunkStorage (world): All chunks
 are saved
[17:20:55] [pool-4-thread-1/INFO]: ThreadedAnvilChunkStorage (DIM1): All chunks
are saved
[17:20:56] [Server thread/INFO]: Found new data pack vanilla, loading it automat
ically
[17:20:56] [Server thread/INFO]: Reloading ResourceManager: Default
[17:20:57] [Server thread/INFO]: Loaded 524 recipes
[17:21:01] [Server thread/INFO]: Loaded 571 advancements
[17:21:02] [Server thread/INFO]: Preparing start region for dimension minecraft:
overworld
[17:21:03] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:04] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:05] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:06] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:07] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:08] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:09] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:10] [Server thread/INFO]: Preparing spawn area: 0%
[17:21:11] [Server thread/INFO]: Preparing spawn area: 4%
[17:21:12] [Server thread/INFO]: Preparing spawn area: 8%
[17:21:12] [Server thread/INFO]: Preparing spawn area: 12%
[17:21:12] [Server thread/INFO]: Preparing spawn area: 16%
[17:21:13] [Server thread/INFO]: Preparing spawn area: 20%
[17:21:13] [Server thread/INFO]: Preparing spawn area: 24%
[17:21:13] [Server thread/INFO]: Preparing spawn area: 28%
[17:21:13] [Server thread/INFO]: Preparing spawn area: 32%
[17:21:14] [Server thread/INFO]: Preparing spawn area: 36%
[17:21:14] [Server thread/INFO]: Preparing spawn area: 40%
[17:21:14] [Server thread/INFO]: Preparing spawn area: 44%
[17:21:15] [Server thread/INFO]: Preparing spawn area: 48%
[17:21:15] [Server thread/INFO]: Preparing spawn area: 52%
[17:21:15] [Server thread/INFO]: Preparing spawn area: 56%
[17:21:16] [Server thread/INFO]: Preparing spawn area: 60%
[17:21:16] [Server thread/INFO]: Preparing spawn area: 64%
[17:21:16] [Server thread/INFO]: Preparing spawn area: 68%
[17:21:17] [Server thread/INFO]: Preparing spawn area: 72%
[17:21:17] [Server thread/INFO]: Preparing spawn area: 76%
[17:21:17] [Server thread/INFO]: Preparing spawn area: 80%
[17:21:18] [Server thread/INFO]: Preparing spawn area: 84%
[17:21:18] [Server thread/INFO]: Preparing spawn area: 88%
[17:21:18] [Server thread/INFO]: Preparing spawn area: 92%
[17:21:19] [Server thread/INFO]: Preparing spawn area: 96%
[17:21:20] [Server thread/INFO]: Preparing spawn area: 96%
[17:21:20] [Server thread/INFO]: Preparing spawn area: 100%
[17:21:20] [Server thread/INFO]: Time elapsed: 18734 ms
[17:21:20] [Server thread/INFO]: Done (39.143s)! For help, type "help"
[17:21:20] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more
[17:21:20] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more
[17:21:20] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more
[17:21:20] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more
[17:21:21] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more
[17:21:21] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.util.ConcurrentModificationExcepti
on
        at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_181]        at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:200) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.b(SourceFile:726) [vanilla-1.13.
2-pre.jar:?]
        at so.b(SourceFile:360) [vanilla-1.13.2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.a(SourceFile:681) [vanilla-1.13.
2-pre.jar:?]
        at net.minecraft.server.MinecraftServer.run(SourceFile:584) [vanilla-1.1
3.2-pre.jar:?]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_181]
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_181
]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at java.util.HashMap$EntryIterator.next(Unknown Source) ~[?:1.8.0_181]
        at bnj.E(SourceFile:1162) ~[vanilla-1.13.2-pre.jar:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~
[?:1.8.0_181]
        at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_181]
        at k.a(SourceFile:199) ~[vanilla-1.13.2-pre.jar:?]
        ... 5 more