Add rule to .stignore: ignore folders containing a specific file

Feature
1

Some backup programs use this paradigm to mark ignored folders. It is resistant to folder move/rename, and very convenient to use. I would love to see a similar kind of rule implemented in .stignore syntax like (example syntax):

...
%/.ignorethisfolder
...

Then all folders containing a .ignorethisfolder file would be ignored from sync.

2

I just discovered the issue was opened on github. Not sure what place is best to discuss, so I’m cross-linking.