I'm wondering if we should think about a different implementation of YouTube (or generic websites) video embedding. Iframe is dangerous too, both for privacy concerns and for this example..
The 'old' way of embedding YT with Aeva was to use the embed tags.
I was told that it made it impossible for iOS users to view a video, and asked to change it to the iframe code...
So I did that.
I also changed, also upon request, the YT URL to youtube-nocookie.com to keep privacy ayatollahs quiet (but mostly to avoid sending cookies for nothing, thus saving bandwidth...), and recently found out that my custom Android ROM's anti-ad list had that domain in its list... Making it instantly impossible for me to load any YT videos posted in Wedge or SMF forums.
Funny, eh...? How it's impossible to please everyone, including me...
Regarding thumbnails. If you'll remember, Aeva Media does exactly that for YT embeds posted directly to a gallery album. It generates a thumbnail for the item list.
It works great.
Actually, it looks like Elk is going to do just that, for regular YT embeds. I'm wishing them luck, because writing a generic embed module for multiple video sites is not exactly easy. (And I won't release Aeva for Elk... Not for the reasons you'd think, though.)
Personally, I like thumbnails, too, but in a post context, I'd rather have a video-sized image, and then have the image be replaced with the embed when clicking. This would eliminate the JavaScript-loading mess, but OTOH it requires too many tweaking to attachment code (or gallery code) for it to be something I'd like to implement in Wedge itself... Eh.