Consider: <!DOCTYPE html> <label> <button onclick="alert('bad')">Don't click</button> <div tabindex="0">Click</div> </label> When one clicks on the div with tabindex attribute, the button gets clicked. But it should not, as the div should be considered interactive content [1], and the HTML Standard says that the activation behavior of the label [2] with events targeted at interactive content descendants of label must be a no-op. Previously Chrome and Firefox behaves similarly to Chrome, but whatwg/html#5414 [3] reaffirms the spec, and Chromium CL 2122369 [4] implements the spec behavior. I plan to implement this change in Firefox as well [5]. We should align once Chrome ship this change. More tests are available at [6]. [1]: https://html.spec.whatwg.org/C/#interactive-content-2 [2]: https://html.spec.whatwg.org/C/#the-label-element:activation-behaviour-2 [3]: https://github.com/whatwg/html/issues/5414 [4]: https://chromium-review.googlesource.com/c/chromium/src/+/2122369 [5]: https://bugzilla.mozilla.org/show_bug.cgi?id=1628500 [6]: https://github.com/web-platform-tests/wpt/pull/22749
<rdar://problem/61484026>
This is apparently not web-compatible, according to https://crbug.com/1069615.