Welcome.
The discord is linked on the home page:
https://www.project1999.com/index.php
There is a green channel.
There is a "Green bugs" section on these forums, but if you are new here it may be good to just ask people in discord first to make sure what you are curious about is actually a bug. Memories from 20 years ago can be hazy. Search the forums before posting a bug, there's also a wiki that often explicitly describes behaviors for various mobs/items/etc. And this page which can show you a behavior you expect may not actually be in game until a certain era.
http://wiki.project1999.com/Patch_notes
There's also a normal "Bugs" section for issues that apply to both green and blue server.
There is a huge influx of not-a-bug posts there and I'm sure all the noise does not help the developers in their final crunch.