Support for the multi-level list styles

[jswiderski]

📝 Provide a description of the new feature

[UPDATED by @Witoso, 2023-09]

This feature request is about introducing support for multi-level lists, known from MS Word as:

Context

This list type is very common in legal documents. The numbering is often used for referencing in the text of a specific parts of the document. List items are frequently headings.

Potential scope

• This should be one of the styles that this available for choosing in the editor's UI by a user.
• It should be detectable on the paste from Word (potentially with GDoc as well).
• It should work with Import from Word / Export to Word.
• It should work with the Export to PDF.
• Integration with Table of Contents as list items can be headings.
• The solution should be performant, as legal documents tend to be large.
• Possible integrations with anchors (when available).

Out of scope

• Custom levels. We don't plan to support the custom multi-level right now.
  • But the solution we pick may have an effect on the future possibilities in this area.

Discovery so far

• After initial prototypes, we haven't one “standard” implementation that works well across browsers.

---

If you'd like to see this feature implemented, add a 👍 reaction to this post.

[jswiderski]

Similar issue - #10792