I can't believe I'm writing this in 2019. It has been asked for years and several times on this wishlist, but is constantly misunderstood/ignored from anybody at webflow.
If you do a front-end editing as cool as yours, don't expect the user to upload pdfs to a dropbox or similar and then link to their domain. This is stupid, unprofessional and plain lazy from your side. Sorry guys. But I'm pissed!
We're loosing clients to other CMS. Really! - So giddy guys, pleeeeeeeease!