Solved IntelliJ VCS - greyed out files?

Hi all! I'm completely new to GitHub and Version Control on IntelliJ IDEA. I've been running into an issue lately:

I'm not sure why, but there are files which won't appear in my Default Changelist, and those are coloured grey.
(Image: default changelist. a lot of files missing!)


(Image: class files, some coloured blue and others gray.)


I couldn't find a solution on the web, I must've done something wrong during setup or during development.
Both of my projects are outdated on GitHub due to this issue.

Help is much appreciated. Thank you! I sincerely apologise if I come across as a complete moron.

 

Oh my. I'll check that out. Thanks for the observation

 

Thank you very much for your help. Problem solved.