Oprah LOVES Facebook Live -- despite some very troubling events this week -- and even bemoans that it wasn't around in the 25 years O talked for a living.

We got the queen Wednesday in D.C., where she sang the praises of the social media platform and her new movie, of course.

Oprah never mentioned the Facebook killer, but did say Facebook needed to be properly managed. That said, she clearly views it as a game changer.

Now ... when is her HBO movie on again? Right, Saturday, 8 PM.