Not working on WP 4.3.1

What Youtube URL are you trying with?

am having the same problem, and it doesn’t matter which YT video I insert.
When I first installed plugin a few months ago it worked perfectly. Now not.
Have also disabled all other plugins on the site to see if there’s a conflict, and have the same result. So it’s seems it is either YT or WP.

I’m not managing to recreate.

I’ve used video urls in the two following structures:

https://www.youtube.com/watch?v=WsQEK4P5DLM
https://vimeo.com/146834156

Both created the featured image upon publish or save.