Integrate FormControlRange hooks into text controls (input/textarea)

[stephanieyzhang]

FormControlRange is 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

• WhatWG discussion: FormControlRange Interface #11478

• Corresponding DOM Spec PR: Add FormControlRange interface dom#1404

• Corresponding CSSOM PR: [cssom-view-1] Add FormControlRange geometry APIs (getClientRects/getBoundingClientRects) w3c/csswg-drafts#12904

• At least two implementers are interested (and none opposed):

  • Microsoft Edge
  • WebKit: FormControlRange - Live ranges for <input> and <textarea> WebKit/standards-positions#541
  • Mozilla: FormControlRange - Live ranges for <input> and <textarea> mozilla/standards-positions#1289

• Tests are written and can be reviewed and commented upon at:

  • https://wpt.fyi/results/dom/ranges/tentative?label=master&label=experimental&aligned
  • PR to make tests non-tentative: Make FormControlRange tests non-tentative web-platform-tests/wpt#55014

• Implementation bugs are filed:

  • Chromium: https://issues.chromium.org/issues/421421332
  • Gecko: https://bugzilla.mozilla.org/show_bug.cgi?id=1990256
  • WebKit: https://bugs.webkit.org/show_bug.cgi?id=299375

• Corresponding HTML AAM & ARIA in HTML issues & PRs:

• MDN issue is filed: …

• The top of this comment includes a clear commit message to use.

(See WHATWG Working Mode: Changes for more details.)

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/form-control-infrastructure.html ( diff )
/form-elements.html ( diff )
/index.html ( diff )
/input.html ( diff )