This is a mod that allows you to download addons so that unnecessary files do not interfere with their launch. There is also some content that is very often used on the servers.
Everything is the same as in 2a, but now the error has been fixed. Now, if your game freezes and you have a green download, wait until it passes and your game unfreezes. Yes, it's a crutch, but it works great! (but now the server can be easily broken, so play with people, not donkeys).