The author says they don't believe that a lighter version has been shown to reduce engagement.
I, on the other hand, fully believe that.
The recommended lite-youtube-embed project page has a demo of both lite and regular players [0], and the lite version takes noticeably longer to start playing the video.
Every additional millisecond of load time will reduce engagement, and here the difference is more on the order of hundreds of milliseconds or more.
The longest segment of a domain name is 63 characters. The maximum length of an HTTPS certificate commonName is 64 characters.
This caused Cloudflare, Vercel, and Netlify to be unable to use Let's Encrypt to sign HTTPS certificates (because they used the domain name as the commonName), but Zeabur can use Let's Encrypt to sign HTTPS certificates.
Finally, the Cloudflare certificate was switched to Google Trust Services LLC to successfully sign.
Additionally, the CN is limited to at most 64 characters, while SANs can be significantly longer. This means that the CN is not only redundant, but actively restrictive: a certificate which has a Common Name cannot contain only very long domain names, because none of them would fit in the CN. For these reasons, the BRs state that for Domain Validated certificates, the Common Name field is "not recommended".