title: iOS15 Webview using `Video` causes crashes - `WebAVPlayerController valueForUndefinedKey - playingOnMatchPointDevice `
body: <p>iOS15 Webview's HTML using <strong>Video</strong> tag, the following crash occurs, does anyone know what is the reason for this?</p>
  <blockquote>
  <p>[&lt;WebAVPlayerController 0x282f41420&gt; valueForUndefinedKey:]: this class is not key value coding-compliant for the key playingOnMatchPointDevice.</p>
  </blockquote>