ConcurrentModificationException while removing more then 1 potion effect

[SHADOWDANCH]

Glowstone commit: https://github.com/GlowstoneMC/Glowstone/commit/b3b6502f64772bdde3d397c29e5d4d0386c06836 If try remove all player effects and he already have more the 1 potion effect active ConcurrentModificationException throw. Can be reproduced with command /effect name clear or code

for (PotionEffect potionEffect : player.getActivePotionEffects()) {
     player.removePotionEffect(potionEffect.getType());
}

Stacktrace:

[SEVERE] Exception while executing command: /effect SHADOWDAN_ clear
org.bukkit.command.CommandException: Unhandled exception executing 'effect SHADOWDAN_ clear' in net.glowstone.command.minecraft.EffectCommand(effect)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:161)
        at net.glowstone.GlowServer.dispatchCommand(GlowServer.java:1903)
        at net.glowstone.entity.GlowPlayer.lambda$chat$15(GlowPlayer.java:2286)
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.util.concurrent.FutureTask.run(Unknown Source)
        at net.glowstone.scheduler.GlowTask.run(GlowTask.java:144)
        at net.glowstone.scheduler.GlowScheduler.pulse(GlowScheduler.java:196)
        at net.glowstone.scheduler.GlowScheduler.lambda$start$0(GlowScheduler.java:122)
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
        at java.util.concurrent.FutureTask.runAndReset(Unknown Source)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(Unknown Source)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
Caused by: java.util.ConcurrentModificationException
        at java.util.HashMap$HashIterator.nextNode(Unknown Source)
        at java.util.HashMap$ValueIterator.next(Unknown Source)
        at java.util.Collections$UnmodifiableCollection$1.next(Unknown Source)
        at net.glowstone.command.minecraft.EffectCommand.execute(EffectCommand.java:67)
        at net.glowstone.command.minecraft.GlowVanillaCommand.execute(GlowVanillaCommand.java:155)
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:151)
        ... 14 more

[SHADOWDANCH]

Possible solution: use ConcurrentHashMap for storing player potion effects instead just HashMap (Looks like it work ok).