I created a GitHub repository and made a .gitmodules file directly from GitHub's web source editor. When I then cloned the repo, I noticed the submodules in .gitmodules were not being initialized.
I think I tried almost all commands possible, including update, init, update --init and so on. Is there a way to use current .gitmodules file, not submodules add?
Writing a submodule isn't enough.
Then, when you push that to your upstream repo on GitHub, the project page will display those special entries as a green folder.