Another Thread safety fix following Gregor's idea but implemented more efficient without an access widener

Author: VoidXWalker

src/main/java/me/voidxwalker/anchiale/mixin/PlayerInstanceMixin.java

@@ -0,0 +1,24 @@
+package me.voidxwalker.anchiale.mixin;
+
+import net.minecraft.server.PlayerWorldManager;
+import net.minecraft.server.network.ServerPlayerEntity;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Mutable;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+@Mixin(targets = "net/minecraft/server/PlayerWorldManager$PlayerInstance")
+public class PlayerInstanceMixin {
+    @Mutable @Shadow @Final private List<ServerPlayerEntity> field_8885;
+
+    @Inject(method = "<init>",at=@At("TAIL"))
+    private void modifyField_8885(PlayerWorldManager i, int j, int playerWorldManager, CallbackInfo ci){
+        field_8885 = new CopyOnWriteArrayList<>();
+    }
+}

src/main/resources/anchiale.mixins.json

@@ -5,7 +5,8 @@
   "compatibilityLevel": "JAVA_8",
   "mixins": [
     "IntegratedServerMixin",
-    "PlayerManagerMixin"
+    "PlayerManagerMixin",
+    "PlayerInstanceMixin"
 
   ],
   "injectors": {