fix video stutters on desktop

src/ui/component/fileViewer/internal/player.jsx

@@ -88,7 +88,6 @@ class MediaPlayer extends React.PureComponent<Props, State> {
   }
 
   componentWillUnmount() {
-    document.removeEventListener('keydown', this.togglePlayListener);
     const mediaElement = this.mediaContainer.current.children[0];
     if (mediaElement) {
       mediaElement.removeEventListener('click', this.togglePlay);
@@ -139,11 +138,8 @@ class MediaPlayer extends React.PureComponent<Props, State> {
     // Render custom viewer: FileRender
     if (this.isSupportedFile() && downloadCompleted) {
       this.renderFile();
-    }
+    } else {
       // Render default viewer: render-media (video, audio, img, iframe)
-    else {
-      // Temp hack to help in some metadata loading cases
-      setTimeout(() => {
       const currentMediaContainer = this.mediaContainer.current;
 
       // Clean any potential rogue instances
@@ -160,7 +156,6 @@ class MediaPlayer extends React.PureComponent<Props, State> {
         { autoplay: true, controls: true },
         renderMediaCallback.bind(this)
       );
-      }, 300);
     }
 
     document.addEventListener('keydown', this.togglePlay);
@@ -225,7 +220,14 @@ class MediaPlayer extends React.PureComponent<Props, State> {
       return;
     }
     event.preventDefault();
-    const mediaElement = this.mediaContainer.current.children[0];
+
+    const mediaRef = this.mediaContainer.current;
+
+    if (!mediaRef) {
+      return;
+    }
+
+    const mediaElement = mediaRef.children && mediaRef.children[0];
     if (mediaElement) {
       if (!mediaElement.paused) {
         mediaElement.pause();
@@ -352,7 +354,7 @@ class MediaPlayer extends React.PureComponent<Props, State> {
         {loadingStatus && <LoadingScreen status={loadingStatus} spinner={isLoading} />}
         {isFileReady && <FileRender claim={claim} source={fileSource} mediaType={mediaType} />}
         <div
-          className="content__view--container"
+          className='content__view--container'
           style={{ opacity: isLoading ? 0 : 1 }}
           ref={this.mediaContainer}
         />