They’re fine asking here.
There are some specific m1 instructions we wrote that we reference on the rails forum in this guide.
I’d have to look on my m1 air later, and maybe my fellow coworks who recently setup new macs might know better if this is even still needed, but there is an example of how to point to a branch in step 7:
gem 'mini_racer', github: 'rubyjs/mini_racer', branch: 'refs/pull/186/head'
So you would edit this line in your local version of discourse/Gemfile:
and then run bundle install.