GitHub上のDiscourseリポジトリをフォークしました。サイト上の既存のDiscourseインストールをこれに置き換えるにはどうすればよいですか?

Indeed, I was originally doing this, but once the plugin was integrated into the core, I am no longer able to modify it. Unfortunately, the suggested solutions also proved ineffective: Overriding user_guardian.rb in a plugin (no fork necessary!) - #24 by kuaza