As they say “This is not a fork. This is a repository of scripts to automatically build Microsoft’s
vscode repository into freely-licensed binaries with a community-driven default configuration.”
Microsoft’s code includes telemetry and tracking code. The code built here is the same as Microsoft’s but with that telemetry and tracking code removed. Also it includes builds for both ARM (32 and 64-bit) which you don’t get from Microsoft.
The Docs page provides info on how to copy JSON bindings from Visual Studio Code to VSCodium. I shall be giving this a try. Much as I like the code.headmelted.com Visual Studio Code, it doesn’t appear to be updated very often whereas VSCodium seems to be built every night.