According to your testing, does the issue occur with ONLY Immersive Portals mod installed?

Yes

Forge Version

40.1.84

ImmersivePortals Version

1.4.12-mc1.18.2

Latest Log

https://pastebin.com/raw/xarkjxry

Crash Report (if applicable)

No response

Steps to Reproduce

1. Install the mod in the server
2. Join the game
3. instantly kicks you out of the game

What You Expected

I expected to join the server

What Happened Instead

When you join, it says loading world and then it kicks you

Additional Details

No response

Please Read and Confirm The Following

• I have confirmed this bug can be replicated without the use of Optifine.
• I have confirmed the details provided in this report are concise as possible and does not contained vague information (ie. Versions are properly recorded, answers to questions are clear).
• I have confirmed this does not happen on the fabric version (If it does please report to here instead).
• I have confirmed I'm not using a hybrid server (Magma, Cauldron) or a different (non official) Forge Server release.
• I have confirmed this issue is unique and has not been reported already.

This report does not meet any requirements. Please share the full log.

Ok sorry.
latest.log

I have tested it in another server without any mods and it shows the same error

Please send a new log if there are still problems. The error you get is normal and only happens in the last tick of a server before it exists.

Have used Magma right of other hybrid server?

Using magma is not Supported.

This problem is not caused by ImmersivePortalsModForForge, an attempt has been made in another project to fix it. see IzzelAliz/Arclight#862