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Issue description:

when loading in game crashes

Steps to reproduce:

1. open minecraft
2. join the server

Version (make sure you are on the latest version before reporting):

Forge: 1.16.5
Mekanism: 1.16.4
Other relevant version:

If a (crash)log is relevant for this issue, link it here: (It's almost always relevant)

https://pastebin.com/AbVhnQcc

Fast answer: Optifine is the issue. Update optifine and Mekanism to the latest version, then it should be fixed.