As you can see from my repository, the url of the submodule is designated as the relative value.
path = JSSoft.Library
url = …/JSSoft.Library.git
path = JSSoft.Library.Commands
url = …/JSSoft.Library.Commands.git
When url is an absolute path, click on the submodule on the web to go directly to the submodule repository.
However, if url is relative, submodule clicks are not possible on the web.
I wonder if it is not implemented yet or if there is another way.