[1.16.5] Server crashed because ConcurrentModificationException

[0XPYEX0]

Before reporting:

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Also, please give this issue a descriptive name that contains the game version in the title, eg.: "[1.16] Distillation Tower Interaction Crash"

Description of the issue

An error occurred when the server started, and it could not be started.
I guess this may caused by List is out of sync caused by asynchrony ? idk...

Versions and Modlist

Minecraft: 1.16.5
ImmersiveEngineering: 5.0.0-135
ImmersivePetroleum: 3.3.0-4
ModList: Following the crash report

Crash Log

https://paste.ubuntu.com/p/tnnhpn6577/

Screenshot(s)

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(Perhaps you could even reference them in that section too)

Thanks for your reply!!!

[0XPYEX0]

I deleted some mods:
ClientTweaks
drippyloadingscreen
fancymenu
konkrete
performant
ponderjs
shutupexperimentalsettings
Tips

And it works well now...
Maybe they have a conflict?
These are some mods that should only be loaded in Client, I put them to Server wrongly

[0XPYEX0]

It crashed again, and I try to use ImmersivePetroleum-3.3.0-6, it crashed too:
https://paste.ubuntu.com/p/VbrygcqyzD/

[mindforger]

the source(meaning the offending object in world) of both crashes seems unrelated, the later one happened while spawning something from IP in the nether while generating a new chunk

[0XPYEX0]

They all happen when the server is starting

[mindforger]

did you change/update/replace/add a mod recently?

[0XPYEX0]

Just delete the mods that should only be loaded in Client,and update ImmersivePetroleum to 3.3.0-6

[mindforger]

the second crash report went off by some data fixer and that is why it might be unrelated to the first crash

at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:1104) ~[?:?] {re:mixin,pl:accesstransformer:B,pl:runtimedistcleaner:A,re:classloading,pl:accesstransformer:B,pl:mixin:APP:kubejs-common.mixins.json:MinecraftServerMixin,pl:mixin:A,pl:runtimedistcleaner:A}

this seemed to stem from kubejs, i suppose their data data fixer interaction is broken too ...

[0XPYEX0]

So...What can I do...?

[0XPYEX0]

I got a new one:
https://paste.ubuntu.com/p/PSbJMxp384/