The video can start playing when you "permit" it to by giving it a suitable input event. Apparently a mouse motion is enough. It doesn't have to be a click.

The video can start playing when you "permit" it to by giving it a suitable input event. Apparently a mouse motion is enough. It doesn't have to be a click. There is a bugzilla item about this somewhere, where the FF devs think that is a good interface. Upton Sinclair anyone?