AVPlayer disappeared When entering the foreground mode after entering the background mode.
It works correctly when playing .mp4 files, but this issue occurs when playing .m3u8 files.
This problem occurs in iOS 14 but not iOS 13.
After AVPlayer play correctly, it is paused when entering the background mode.
When entering the foreground mode, the AVPlayerLayer disappeared, and only a black screen is displayed.
This happens with both AVPlayerLayer and AVPlayerViewController.
It works correctly when playing .mp4 files, but this issue occurs when playing .m3u8 files.
This problem occurs in iOS 14 but not iOS 13.
After AVPlayer play correctly, it is paused when entering the background mode.
When entering the foreground mode, the AVPlayerLayer disappeared, and only a black screen is displayed.
This happens with both AVPlayerLayer and AVPlayerViewController.
