@robryk Because that's how I block Mastodon/Twitter from selecting random and often inappropriate images from linked pages, which they both may do at any time without any way for the user to prevent it, other than include their OWN image.
@lauren Ah. Yeah, that happens on the receiving side (i.e. the instance that receives such a post) and not on your instance's side, so there's really ~nothing else you can directly do about that :/