This is from the day 1 I have KiCAD … (version 5.0 till 7.0.5)
I have a project folder with 1 master project, that contains other 2 projects (sub-projects)
With the project Manager, I can easily navigate down the folders.
But I can navigate upwards.
So, when I enter a subfolder and I open that project, I cannot be back to the Main folder to open for instance the main project.
No, the stable v7.0.x will only get bugfixes, no new features/enhancements.
You could open a feature request (and see how much support/thumbs-up you get) for v8, but I think the chances for implementation are limited. In the past there was the opinion to not put too much work into the main manager, these auxiliary program part should not be developed into some “file manager” tool.
(The gitlab search is not so good - I didn’t found some of these old discussions instantly, so no link).