Unnest list item with children using Backspace at start of line

[baranka144]

Problem

In ProseMirror (and consequently Tiptap), pressing Backspace at the very beginning of a list item that has nested children does not unnest the item as one might intuitively expect. Instead, it exhibits the following behavior:

1. Pressing Backspace selects the content/line directly above the list item.
2. Pressing Backspace again deletes that selected content.

Example:
Some preceding text

• List Item 1

  • Nested Item 1.1

  Pressing Backspace with the cursor at the start of "List Item 1" will select "Some preceding text". Pressing Backspace again will delete "Some preceding text".

This behavior is inconsistent with how Backspace works at the start of a list item without children (where it typically unnests the item).

Desired Behavior

We propose that pressing Backspace at the very beginning of a list item that has nested children should behave identically to the existing Shift + Tab keyboard shortcut for that same item.

Specifically, it should unnest the current list item, bringing it and all its nested children up one level in the list hierarchy.

Using the previous example:
Some preceding text

• List Item 1
  • Nested Item 1.1

Pressing Backspace (or Shift + Tab) should result in:
Some preceding text
List Item 1

• Nested Item 1.1

I understand that the current Backspace behavior likely originates from ProseMirror's default keymap handling. However, I believe it should be possible to adjust this behavior specifically within Tiptap to achieve the desired unnesting action described above.

Thank you!

Use Case

Tiptap already provides the Shift + Tab / Tab combinations for managing list indentation, and Shift + Tab correctly unnests items with children. Aligning the Backspace behavior at the start of such items with the Shift + Tab behavior would:

1. Improve Intuitiveness: Users often expect Backspace at the start of a line/block to modify the indentation or structure of that block.
2. Increase Consistency: It makes the Backspace behavior consistent regardless of whether a list item has children or not, unifying the unnesting action.
3. Provide a Natural Alternative: Offers a more common keyboard shortcut (Backspace) for a frequent list editing action.

Type

New extension