This is almost definitely not going to actually allow tweets to be any longer.
My bet is that it manifests as some kind of text attachment. Just as you're currently able to attach images, video, and all sorts of random junk via 'cards', you'll now be able to attach a text post.
My bet is that it manifests as some kind of text attachment. Just as you're currently able to attach images, video, and all sorts of random junk via 'cards', you'll now be able to attach a text post.