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!
P.S. If you get
Instance update failed because: Instance has conflicting dependencies.
This is a superficial error by multimc, click Launch from the instance console window and it will launch just fine.