move xxx.player = nil; from applicationDidEnterBackground to applicationWillResignActive works with this solution https://stackoverflow.com/questions/64055966/ios-14-play-audio-from-video-in-background

I am using XCode 12 Release. When I am editing storyboard, each every action, I have to wait few seconds(XCode uses cpu 100%)

I have never seen this problem at iOS 13

something weird.. AVPictureInPictureController.isPictureInPictureSupported() => true but AVPictureInPictureController.isPictureInPicturePossible => false and [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] AVPlayerController's PIP buttons is well but PIP does not start automatically when go to home

if AVPictureInPictureController.isPictureInPictureSupported(), let player = self.player{       let layer = AVPlayerLayer.init(player: player);       self.pipController = AVPictureInPictureController.init(playerLayer: layer);       self.pipController?.delegate = self;       print("[\(#function)] create pip player[\(self.player?.description ?? "")] pip[\(self.pipController?.description ?? "")] allow]\(self.playerViewController.allowsPictureInPicturePlayback)]");       if self.pipController?.isPictureInPicturePossible ?? false{         self.pipController?.startPictureInPicture();         print("[\(#function)] start pip[\(self.pipController?.description ?? "")]");       }       self.pipObserver = self.pipController?.observe(\AVPictureInPictureController.isPictureInPicturePossible, options: [.new], changeHandler: { (pip, change) in //.initial,         print("[\(#function)] isPictureInPicturePossible[\(change.newValue.debugDescription ?? "")]");       });       //     } => [startPlayingInPIP()] create pip player[<AVPlayer: 0x281a7f920>] pip[<AVPictureInPictureController: 0x283ce5020>] allow]true] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] .... [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(true)] [startPlayingInPIP()] isPictureInPicturePossible[Optional(false)] what's this??