Kind of, in that embedding anything from a site you can’t trust is inherently risky, but I’d say it’s not actually that bad, for two reasons:
iframes are much better sandboxed than they once were, and are much safer now than their reputation suggests
you probably wouldn’t be embedding from any old instance; I assume you could embed from an instance you use and trust as long as the post is federated to it
Can you post snippets of mastodon posts on websites like you can tweets?
You mean embedding posts or something else? https://fedi.tips/how-to-embed-mastodon-posts-on-a-website/
But isn’t that inherintly dangerous? I don’t exactly trust any random fedi server to embed it in my website.
Kind of, in that embedding anything from a site you can’t trust is inherently risky, but I’d say it’s not actually that bad, for two reasons: