Finding Path/Directory of the Project

This may sound weird, but I have multiple copies of a project all with the same filename with tiny differences in its content. Is there a convenient way to obtain the directory or the path of the currently opened project?

I tried to open a “Save As” dialog, but the directory seems to be not the project directory. “Project Info” doesn’t display this metadata.

On my Windows system, Save As does indeed start in the project’s folder.

On Mac, I believe you can Cmd+click the filename to show the location.