Change it, but no difference with the 1st video, but the 3rd video is able to generate the thumbnail now.
errr … on the 2 pages you linked I never saw the thumbnail not shown; either it was a LYTE video (with thumb) or it was a YT embed (again with thumb)?
confused now..
https://www.theholidaystory.com/bakkhali-tour
this is the perfect page which generates the thumb. it’s a youtube direct embed. No <div class=“video-container”> code embad.
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problem in:-
https://www.theholidaystory.com/joydev-kenduli-mela-birbhum-baul
its has 3 videos 1st is the <div class=“video-container”> and 2 and 3 is youtube direct embed. only 3rd is able to genarate the thumb.
All thumbnails load for me Ruma;

Based on what you write, your issue is not with the LYTE vids, but with the YT ones?
Happy new Year.
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I can see only 1 video is able to generate the thumb, out of 3, because watch this “video on youtube” link is missing on both 2 videos.
Happy new year to you as well Ruma! All the best for 2021 for you and your loved ones! 🙂
Now back to the videos; your original problem was video’s with a grey background/ thumbnail, is that problem gone now?
only one problem I find now:-
“thumbnail generation problem” in a few videos. youtube and ifrem both kind of embed.
so no more grey backgrounds, right?
now re. some video’s still being Youtube embeds; provided the space is removed and the quotes are normal " ones, it _should_ work. if not I guess you’ll have to change those into the way you’re doing for the vids that do work (a youtube link?)
Ya, I tried but no luck. It only works with youtube embed. Anyway thanks.