But in the scenario of lemmy / mastodon, you only ever interact with your chosen frontend / instance and it only communivates to facebook through activitypub not through the general web standards. Even if facebook were to just embed a bunch of js code as an activitypub text feed, your chosen instance would still have to choose whether or not to render it by default, or to give you the option, or to block it entirely.
You don’t have to if they visit you themselves
But in the scenario of lemmy / mastodon, you only ever interact with your chosen frontend / instance and it only communivates to facebook through activitypub not through the general web standards. Even if facebook were to just embed a bunch of js code as an activitypub text feed, your chosen instance would still have to choose whether or not to render it by default, or to give you the option, or to block it entirely.