This is something that's truly atrocious about the move to digital-only copies. On paper, I can mark things up, initial them, send them back. The digital copies let me sign, and that's it. There's no in-band way to indicate that a section should be changed, no way to clarify wording. It's a system designed for contracts of adhesion, and nothing else. Heck, most of them will automatically scroll to the next place for a signature, implying that you shouldn't actually read what you're signing.