Bug 299375 – Implement OpaqueRange

• Status: NEW
• Component: DOM

Implement FormControlRange -- a specialized, live AbstractRange subclass for <input>/<textarea> value space. It enables range-based operations in native controls while restricting standard Range mutations to preserve encapsulation. It integrates cleanly with existing selection/editing behavior and closes a long-standing gap.

Explainer: https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/FormControlRange/explainer.md

Ongoing WHATWG discussion thread: https://github.com/whatwg/html/issues/11478

WebKit Standards Link: https://github.com/WebKit/standards-positions/issues/541

[Radar WebKit Bug Importer]

<rdar://problem/161658720>

[Radar WebKit Bug Importer]

<rdar://problem/161658759>

(In reply to stephanie.zhang from comment #0)

Updating this bug to reflect the current proposal.

The proposal has evolved from FormControlRange into OpaqueRange. OpaqueRange is a specialized, live AbstractRange subtype whose boundary points reference internal nodes within host-defined elements (for example, <input>/<textarea> today, with a path to custom elements in the future). It enables range-based operations over encapsulated content while avoiding exposure of internal DOM nodes.

The proposal also updates AbstractRange so startContainer/endContainer can be null, allowing OpaqueRange to return null for those getters while Range and StaticRange continue to return nodes.

Updated explainer:
https://github.com/MicrosoftEdge/MSEdgeExplainers/blob/main/OpaqueRange/explainer.md

Current specification work:
https://github.com/whatwg/dom/pull/1404
https://github.com/whatwg/html/pull/11741

Relevant WHATWG discussion:
https://github.com/whatwg/html/issues/11478

WebKit standards position issue:
https://github.com/WebKit/standards-positions/issues/541