Feature Req: Notebook-Specific Tags

[TessaI159]

I would love to be able to add tags that are specific to a single notebook. I'm a mathematics student and I have lots of theorems/lemmas/corollaries, but theorem 1 in the abstract algebra notebook may be completely different than theorem 1 in the real analysis notebook.

[pragmatically-dev]

This would be a game-changer feature for organizing better!

[zelomel]

Maybe you can use bookmarks ?