[12:44:03] [Server thread/ERROR]: Could not pass event ChunkUnloadEvent to testplugin v1.0-SNAPSHOT
org.bukkit.event.EventException: null
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:310) ~[spigot-api-1.21-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[spigot-api-1.21-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:601) ~[spigot-api-1.21-R0.1-SNAPSHOT.jar:?]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:588) ~[spigot-api-1.21-R0.1-SNAPSHOT.jar:?]
        at net.minecraft.world.level.chunk.Chunk.unloadCallback(Chunk.java:590) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.PlayerChunk.lambda$updateFutures$7(PlayerChunk.java:324) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.PlayerChunkMap$CallbackExecutor.run(PlayerChunkMap.java:167) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.PlayerChunk.a(PlayerChunk.java:334) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.ChunkMapDistance.lambda$runAllUpdates$1(ChunkMapDistance.java:128) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[?:?]
        at net.minecraft.server.level.ChunkMapDistance.a(ChunkMapDistance.java:127) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.ChunkProviderServer.s(ChunkProviderServer.java:290) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.ChunkProviderServer$b.B(ChunkProviderServer.java:614) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.level.ChunkProviderServer.d(ChunkProviderServer.java:286) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.bv(MinecraftServer.java:1258) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.B(MinecraftServer.java:1242) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.util.thread.IAsyncTaskHandler.b(SourceFile:145) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.b(MinecraftServer.java:1207) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.v_(MinecraftServer.java:1214) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.y(MinecraftServer.java:1078) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:318) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at java.base/java.lang.Thread.run(Thread.java:1583) [?:?]
Caused by: java.lang.IllegalStateException: Chunk not there when requested: Unloaded chunk
        at net.minecraft.server.level.ChunkProviderServer.a(ChunkProviderServer.java:156) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.world.level.World.a(World.java:298) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at net.minecraft.world.level.IWorldReader.a(SourceFile:156) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at org.bukkit.craftbukkit.v1_21_R1.CraftChunk.getHandle(CraftChunk.java:87) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at org.bukkit.craftbukkit.v1_21_R1.CraftChunk.getTileEntities(CraftChunk.java:183) ~[spigot-1.21-R0.1-SNAPSHOT.jar:4272-Spigot-34bd42b-76f59e3]
        at me.taucu.testplugin.TestPlugin.onChunkUnload(TestPlugin.java:18) ~[?:?]
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[?:?]
        at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[?:?]
        at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:306) ~[spigot-api-1.21-R0.1-SNAPSHOT.jar:?]
        ... 21 more 

    @Override
    public void onEnable() {
        Bukkit.getPluginManager().registerEvents(this, this);
    }

    @EventHandler
    public void onChunkUnload(ChunkUnloadEvent e) {
        for (org.bukkit.block.BlockState state : e.getChunk().getTileEntities()) {
            //weeeeeee
        }
    }