[2021] Mod Checksum Different in a Linux Machine

That thread was from 2014! I would assume the case sensitivity issue there was resolved long ago, but is that what you are saying is the case here?

FYI I know nothing about modding - have you asked in the User Mods forum?  

The key question is whether it just affects your machine, or is a general problem in Linux - I would have thought we'd have had more reports in the last 7 years if this was a general issue!

Does this affect every mod you try, or just some or one?  

Not sure whether that would be considered a game/launcher bug, or a requirement on the Mod authors to use consistent case in their mods!