Notebook Outline / Table of Contents

[amit1rrr]

Problem

Notebooks can be long and require a lot of scrolling around to properly review. Users have asked for outline view.

Solution

Table of contents (ToC) that shows clickable nested markdown headers would help reviewers to

1. Just look at the notebook outline / high level structure
2. Click on specific parts to quickly navigate & review just that section - also can quickly jump back & forth between various sections of a given notebook

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Feel free to upvote/downvote the issue indicating whether you think this is useful feature or not. I also welcome additional questions/comments/discussion on the issue.

[amit1rrr]

Example would be outline section shown in VSCode notebooks. Screenshot below.

Open Questions

1. Should code cells be shown in the outline? If yes, how / what should the outline item say?
2. Should comment counts be shown alongside outline item text? If yes, should it be total comment count or just the open/unresolved comment count?
3. Should diff indicators (++ / -- or green / red squares) be shown on the outline item to visually indicate which part of the notebook has diff?
4. Is this outline useful for small diffs? Should we show it for ALL diffs? It's most useful for newly added files.