Bug 251207 – REGRESSION (Safari 16.3-STP161): video element is not expanded to fullscreen in certain case that by DOM Fullscreen API

• Status: RESOLVED
• Resolution: FIXED
• Component: DOM

[Tetsuharu Ohzeki [UTC+9]]

Created attachment 464667 [details]
screenshot

## Environment

- macOS 13.2 (Intel)
- Safari TP Release 161 (Safari 16.4, WebKit 18615.1.17.6)


## Steps to reproduce

1. Open https://nocebo.jp/html5_video_fullscreen/
2. Scroll to the embed Codepen iframe.
3. Click Big Buck Bunny's thumbnail.


## Actual Result

Safari does not expand "Big Buck Bunny" video to fullscreen.
Please see the screenshot I attached to this.

## Expected Result

- The video should be expanded to fullscreen.
- Safari 16.3 (18614.4.6.1.5) on macOS 13.2 (Intel) expands it to fullscreen

[Tetsuharu Ohzeki [UTC+9]]

The embedded is https://codepen.io/nocebojp/pen/JzYYgx

But this bug is not reproducible if I open it without embedder.

[Tetsuharu Ohzeki [UTC+9]]

This is still happen with Safari TP Release 162 (Safari 16.4, WebKit 18615.1.18.2)

[Radar WebKit Bug Importer]

<rdar://problem/104719780>

[Tetsuharu Ohzeki [UTC+9]]

I think this has been fixed in:

- Safari TP Release 163 (Safari 16.4, WebKit 18615.1.18.100.1)
- Safari TP Release 164 (Safari 16.4, WebKit 18616.1.2)

Thank you!