The url is getting truncated so you are missing part of the query.
The full url is

Hi Jamo, thanks for the hint. I see that with the mouseover - but I thought the dots are perhaps a foundation rule or another secret - I am totally unprofessionell ... Later I will go and tryin SD and your hint may help me to avoid being frustrated.

Thanks Jamo and thanks Wayan - I just previewed it in SD - its working fine - I had to put into the "Video Url" of the Video Platform the full Link like Jamo said =
https://www.youtube.com/embed/YSCGN5yUI … showinfo=0
Now it's working fine.

I tried to change .... showinfo=0 and when typing instead showinfo=-2 (minus 2) the number of youtube links is reduced to 1 only.
Isnt' it possible to suppress the pop up totally ?
Next I will have to learn the HTML Video - perhaps that is what I want...

Please disregard my stupid "tip" - showinfo should only be =0 or =1...