Fix ConcurrentModificationException

README.md

@@ -10,8 +10,15 @@ Purple = End
 This mod utilizes vanilla scoreboard teams to color nicknames.  
 To opt-out of detection you can join any other team.
 
-[CurseForge](https://legacy.curseforge.com/minecraft/mc-mods/dimensional-tracker), [Modrinth](https://modrinth.com/mod/dimensionaltracker)
+## [CurseForge](https://legacy.curseforge.com/minecraft/mc-mods/dimensional-tracker), [Modrinth](https://modrinth.com/mod/dimensionaltracker)
 
 [Discord](https://discord.gg/UY4nhvUzaK)
 
+### Why this mod instead of datapacks?  
+Because of how datapacks work they should check dimensions every tick. It's okay for singleplayer, but on servers it can cause lag.  
+In testing, I saw that it can take up to 30% of MSPT for 10 players:
+![img.png](datapack.webp)
+
+### Example of how it works using Immersive Portals
+
 ![image.webp](image.webp)

gradle.properties

@@ -9,7 +9,7 @@ yarn_mappings=1.20.2+build.1
 loader_version=0.14.22
 
 # Mod Properties
-mod_version=1.0.0
+mod_version=1.1.0
 maven_group=xyz.nikitacartes
 archives_base_name=dimensionalTracker
 

src/main/java/xyz/nikitacartes/dimensionaltracker/DimensionalTracker.java

@@ -36,7 +36,9 @@ private void onServerTick(MinecraftServer server) {
         if (playerCache.isEmpty()) {
             return;
         }
-        playerCache.forEach(playerName -> {
+        LinkedHashSet<String> temp = new LinkedHashSet<>(playerCache);
+        playerCache.clear();
+        temp.forEach(playerName -> {
             ServerPlayerEntity player = server.getPlayerManager().getPlayer(playerName);
             if (player != null) {
                 if (server.getScoreboard().getTeam(player.getEntityName()) == null) {
@@ -54,7 +56,6 @@ private void onServerTick(MinecraftServer server) {
                 }
             }
         });
-        playerCache.clear();
     }
 
     private void onServerStarted(MinecraftServer minecraftServer) {