You can clone with
For html5 video code as following:
<video width="320" height="240" controls>
<source src="movie.mp4" type="video/mp4">
<source src="movie.ogg" type="video/ogg">
Your browser does not support the video tag.
Currently DTCoreText expect "src" attribute in video tag.
added VIDEO end tag handler that extracts SRC from a SOURCE child if …
@yifan finally got around to implementing something for that. Feel free to make the source search smarter ...