Elements
<mux-video>
<mux-audio>
<mux-player>
<mux-player audio>
<mux-player> (cuePoints)
<mux-player> (chapters)
<mux-player> (renditions)
<mux-player> (poster slot)
<mux-player> (audio tracks)
<mux-player> (microvideo theme)
<mux-player> (classic theme)
<mux-uploader>
<mux-uploader> (full-page)
