Should we propose "::caret" pseudo-element to CSS WG?

::caret pseudo-element

Proposal:

::caret pseudo-element is used for rendering "caret-shape:bar", rendering engine uses "font-*" properties to determine height of caret, from font-size and font-family, and width from font-weight and slanted from font-style.

Motivation

::caret pseudo-element allows us:

• Solves #70, height of empty element is specified by ::caret pseudo-element. When editable element gets focus, we can enlarge the element to hold a character having style specified by ::caret pseudo-element rather than height of element.

<style>
::caret { font-size: 20px }
</style>
Below cE should have height for "font-size: 20px" when its get focus.
<div style="height: 0px" contenteditable>
   <span style="font-size: 20px;">foo</span>
</div>

• Font menu; rather than inserting an empty SPAN with inline style, we set properties of ::caret pseudo-element for matching caret shape to next inserted characters.
• Render caret as last typing style; rather than leaving empty element, we can remove empty element, e.g. when user removes character a from <b>a<;/b>, we want to remove <b></b> but caret shape should be thick since next typed character should have bold style.

Note: Term "height" and "width" assumes horizontal writing-mode, on vertical-mode height and width are swapped.

[1] https://drafts.csswg.org/css-ui-4/#caret-shape

Start by reading the proposed ::caret pseudo-element behavior in this issue and the linked CSS UI 4 caret-shape reference. Determine whether the editing task force should forward the proposal to the CSS Working Group, and record the resulting decision or next steps.