Bug 217692 – `beforeinput` event is not fired when selecting an item of autocomplete or password manager

• Status: NEW
• Component: HTML Editing

[Masayuki Nakano]

1. Go to https://d-toybox.com/studio/lib/input_event_viewer.html
2. Choose "<input type="text">"
3. Submit the form below "Test editor beahvior:"
4. Then, you'll see same page, backspace some characters from the last to show autocomplete suggest.
5. Choose one of the list.

Then, `beforeinput` should be fired when replacing the `<input>`'s value, but only `input` event is fired. You can check it with the table below "Events:".

You can similar thing with password manager with choosing "<input type="password">" at #2.

[Radar WebKit Bug Importer]

<rdar://problem/70304782>

[Masayuki Nakano]

FYI: Firefox will ship `beforeinput` with the following hack because of this WebKit's bug and Blink's same bug (https://bugs.chromium.org/p/chromium/issues/detail?id=1051844).

1. Will fire `beforeinput` event when user uses build-in autocomplete etc.
2. Set its `inputType` to `insertReplacementText` as defined by the spec.
3. But make it not cancelable for protecting Firefox users from web apps which unexpectedly blocks default actions of `insertReplacementText`.

https://phabricator.services.mozilla.com/D93206

[sideshowbarker]

Nakano-san, Do you know if we have any relevant WPT tests for this?

[sideshowbarker]

Nakano-san, Is the Chrome behavior for this case spec-conforming?

[Masayuki Nakano]

(In reply to sideshowbarker from comment #3)
> Nakano-san, Do you know if we have any relevant WPT tests for this?

Unfortunately, there is no WPTs because the test driver does not provide a way to work with browsers' UI like a popup of autocomplete.

(In reply to sideshowbarker from comment #4)
> Nakano-san, Is the Chrome behavior for this case spec-conforming?

No, I filed Chromium bug too.
https://issues.chromium.org/issues/40673974