Per spec, only <input>, <textarea>, and form-associated custom elements are barred from constraint validation if "readonly" attribute is present.
<rdar://problem/103843825>
Pull request: https://github.com/WebKit/WebKit/pull/8158
Committed 258485@main (a4eb84de0c69): <https://commits.webkit.org/258485@main> Reviewed commits have been landed. Closing PR #8158 and removing active labels.