[Webkit-unassigned] [Bug 255024] New: Playing Video with Intersection Observer results in "Unhandled Promise Rejection: AbortError: The operation was aborted."

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=255024

            Bug ID: 255024
           Summary: Playing Video with Intersection Observer results in
                    "Unhandled Promise Rejection: AbortError: The
                    operation was aborted."
           Product: WebKit
           Version: Safari 16
          Hardware: All
                OS: iOS 16
            Status: NEW
          Severity: Critical
          Priority: P2
         Component: JavaScriptCore
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: contact at benfrain.com

This works without problem in Chrome and Firefox. Fails on Safari up to, and including Release 166 (Safari 16.4, WebKit 18616.1.6.11). 

The error in the console is "Unhandled Promise Rejection: AbortError: The operation was aborted."

Test page: https://benfrain.com/playground/video-stop-start/index.html

What should happen is that the videos pause as they are scrolled past and play when they are scrolled into view. This mechanism is achieved with this code:


```
function playPauseVideo() {
  let videos = document.querySelectorAll("video");
  videos.forEach((video) => {
    // We can only control playback without insteraction if video is mute
    video.muted = true;
    // Play is a promise so we need to check we have it
    let playPromise = video.play();
    if (playPromise !== undefined) {
      playPromise.then((_) => {
        let observer = new IntersectionObserver(
          (entries) => {
            entries.forEach((entry) => {
              if (entry.intersectionRatio !== 1 && !video.paused) {
                video.pause();
              } else if (video.paused) {
                video.play();
              }
            });
          },
          { threshold: 0.2 }
        );
        observer.observe(video);
      });
    }
  });
}
```

I am unsure if this is a bug or a missing piece of requisite (undocumented) code that only Safari needs?

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