Clipboard, browser extension, or universal autofill for macOS web pages - which is safest

Thanks for the link Evon. Let me be concrete.

I'm staring at a web page. I'm running macOS. I have three choices to enter my credentials: use the clipboard, install and use the browser extension, or use Universal Autofill. One of your security researches is sitting next to me. Assume they know nothing about my computer hygiene practices or the safety of the websites I visit. What choice would they make for me? They have 5 seconds to answer before I explode in frustration.

And, suppose their first choice fails. For example, suppose the browser extension (if that was their first choice) doesn't correctly fill in the fields. Let's assume I haven't exploded yet, but it's very, very close to happening. What would they tell me to try next?

Feels like an action movie.