What it does:
- Removes the need to login if you just want to play offline or on a private server
- There's no check for an update, you're directly catapulted to the main menu or connected to a server
- Additional parameters (f.e. start as maximized window or loading of certain versions from different directories)
What it does not:
How does it work?
Basically this is just mimicking the behavior of the official launcher, except that it removes the online authentication and the update process. I figured most of that out with Trial & Error, that's why it's looking a little bit crude and has debugging output all over the place.
Please consult the README for a thorough documentation on the software.