I keep getting the black screen from Youtube when opening a video. If I reload it comes up.
Then depending what way the wind is blowing part way into the video I get the black screen again.
With this text. "An error occurred. Please try again later (Playback ID:qbc8dExpUdk25U1l)
And below that you get the Learn More. If I disable blocking on that site all works normal with the ads.
Mac OS 10.12.6 Safari 12.0.3