When I really need "Hide my email", it doesn't pop up on Safari on my iphone.

Like many things with Apple passwords options that don't pop up on websites, I also find that "Hide my email" shows up occasionally, but not when I really want to use it, such as on a poll. It's very frustrating. Is there a way to make "Suggest a password" or "Hide my email" show up? I'm always logged in to Apple and have iCloud also.