The address is missing a colon after the https.
Cut and paste, add a colon before // and it works.
edit: the link displayed is different to that embedded in the forum, i.e. "http://https//m.youtube.com/watch?feature=player_embedded&v=qFUZ6oHBft4"
so
https://m.youtube.com/watch?feature=...&v=qFUZ6oHBft4 will get you there.