3.7.16
See screenshots.
If your note is several notebooks deep in a hierarchy, and that hierarchy gets collapsed, you lose all context to what notebook is currently active.
I would love to see each tier highlighted or outlined in some way so I retain contextual understanding where in the hierarchy I am working.
In this example, I am working in 'Notebook level 3-02'. Ideally 'Notebook level 1' would have some contextual indication as would 'Notebook level2' so that as those notebooks are collapsed, I can have a quick means to grok where I am in my gazillion notebooks.

