Video in Interface

I tried adding a YouTube video to an interface but it ends up blank.

a!videoField(
              videos: {
                a!webVideo(
                  source: document(21953,"url")
                )
              }
            )

I tried using this code and for source I tried replacing it with the YouTube video url which didn't work also. Do I need the mp4 of the video in documents or are YouTube videos not compatible?