the contents of wp-content/plugins/wp-youtube-lyte/lyte/lyte-min.js seems corrupted, can you try re-installing the plugin?
I did it but nothing changed :/
still corrupted, might you (or your hoster) have a security “solution” running that removes (replaces) code in .js-files?
lyte-min.js should have this part in it
tH.innerHTML='<iframe id="iF_'+vid+'" width="'+tH.clientWidth*2+'" height="'+aHgh+'
but in your case that becomes
tH.innerHTML='XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX+'" height="'+aHgh+
and that obviously cannot work .. :-/
I ask them and I get back to you. Thanks!
Hello!
I had some back and forth with my host.
Apparently they removed a security check that was interfering with the plugin but I still see the thumbnails grey. What could I do?
you’ll probably have to re-install to ensure lyte-min.js is correct again?
I don’t get your answer, sorry
I tried to re-install but it’s still not working :/
I meant “your question”, sorry
well, lyte-min.js still has some of the code removed, so you will have to get back in touch with your host I’m afraid .. :-/

I’ll do that, thanks! May I just have a bigger image, please?