If it was the full URL (you can see it displayed immediately above that video) then the only reason I can think is that embedding the video inside reply text doesn't always work - I have found this to be the case in the past and so always use the Enter Youtube Link Here... box these days.
Thanks Bibblebub - I just inserted the link into the text ie, not using the UTube link box. As I said earlier, it was my first attempt at a link - I'll know better next time.
Some people have no problem embedding the video in the middle of the reply text but when I tried it (a long time ago) it failed more often that it succeeded so I stick to the tried and trusted method that works every time.
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