pdisplaying ayoutube video test
 

to display the video it is (as Char discovered) for some obscure reason necessary to omit the "s" from the https:// in the full YouTube URL
full URL
https://www.youtube.com/watch?v=b3bgFN7qLvs
omitting the s
OR as EDITED on 1 August to delete everything in front of the www
basically you can't win before I came here today for the last umpteen months the "s" omitted version was NOT displaying go figure or shoot yourself!!
Yours in exasperation Sir John