1503682 - scrollable iframe incorrect focus positioning

Status: RESOLVED INVALID

(Firefox for iOS :: General, defect)

Description

[k.vendrik]

Attachment: Codepen-Demo.MP4

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

Steps to reproduce:

Embedded a form in a scrollable iframe.

Codepen with iframe: https://codepen.io/kvendrik/pen/ePqNvy
Codepen with iframe contents: https://codepen.io/kvendrik/pen/vVoOgq


Actual results:

When focussing some of the fields the focus seems to be on elements that I'm not tapping on, sometimes in completely different positions.


Expected results:

The input that I tap on should focus.

Comment 1

[Justin D'Arcangelo [:justindarc]]

Does this happen in Mobile Safari and/or Chrome for iOS?

Comment 2

[k.vendrik]

Not to this extend as far as I have seen. I have had a simular issue in Mobile Chrome where it happened when the iframe increased in size because a Textarea automatically resized based on its input.

Comment 3

[Catalin Suciu [:csuciu]]

Attachment: codepen-safari.mov

I'm seeing a similar behavior in Safari. Please check the video.

Comment 4

[Justin D'Arcangelo [:justindarc]]

From the above video in Comment 3, it looks like this is also reproducible in Safari. I agree that its a bug, but it seems to be a bug within WKWebView itself since it is not unique to Firefox for iOS. You may want to open a bug in the WebKit bug tracker: https://bugs.webkit.org/

Comment 5

[k.vendrik]

Gotcha makes sense, I've opened a bug here: https://bugs.webkit.org/show_bug.cgi?id=191364.

Comment 6

[k.vendrik]

To clarify:

https://bugzilla.mozilla.org/attachment.cgi?id=9023207
Demonstrates different the cursor having a different position than the input in mobile Safari.

https://bugzilla.mozilla.org/attachment.cgi?id=9021636
Demonstrates the cursor having a completely different position than the input but also demonstrates a different input getting selected than I'm tapping on which is the more concerning bug imo (Mobile FF).

I feel like the latter might still be a Mobile FF specific bug as I don't seem to be getting this behaviour in Mobile Safari, Mobile Chrome seems to sometimes have it but by far not as extreme as in Mobile FF.

Comment 7

[Justin D'Arcangelo [:justindarc]]

This bug is outside of our control as it is a WebKit issue. Thank you for opening an issue in the WebKit tracker. I'm going to close this bug in our tracker since there is nothing actionable on our end.