I'm looking into how various social media services provide embeds and there's either an <iframe> or a some sort of inline preview (makes sense so far) and then... a <script>? That renders the actual embed? Mastodon and Pixelfed do it like this too. Is this how it's always done? Feels odd that people just add these scripts to their websites.
This embed on The Verge? Yep, it actually runs a script loaded from tapbots.social straight on theverge.com 🙈
But then how DO you make an iframe that can resize itself without relying on such scripts?