Edit (2024): You no longer need to follow this guide! Just use PrismLauncher.
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Up to Minecraft 1.17.X I used yusefnapora/m1-multimc-hack, but this stopped working for me starting in Minecraft 1.18. Grabbing random jarfiles from a git repository is a little suspicious, so let's do it safely by getting the libraries from the official LWJGL website!
If you don't have Homebrew installed already, install Homebrew by following the instructions at brew.sh. Then, just open a Terminal and type...
brew install java
Install the latest version of MultiMC from the MultiMC website. Unfortunately, the launcher will have to run with Rosetta. This won't affect game performance.
Create a Minecraft 1.18 instance, right click, edit instance, and go to the versions tab on the left. Click on LWJGL in the list, then click customize on the right. Click edit to open the LWJGL configuration file. Replace the content of the file that opens up with the contents of the file called org.lwjgl3.json
that is attached to this gist (see below).
Have fun!
Credits: An older version of this guide required you to manually download jar files. The updated version uses @mjwells2002's gist that automatically downloads the jar files for you!
There's an issue on the multimc-hack repo that links to https://gist.github.com/mjwells2002/417e1f673794b14c188b6138afb92bd9 , which suggests that instead of downloading individual v3.3.0 JARs by hand, you can use a
downloads.url
property and I guess the relevant dependencies are downloaded automatically (by the launcher?). You should be able to trust the JARs because the JSON in that gist points to the official release packages, I think.