autofill fails for bobsredmill.com

I don't have an account on that site. I was trying to autofill my identity. I selected one from the drop-down list that appears in the field, but it did nothing. I also tried selecting it from the 1Password app. That also failed to fill in. But I kept getting the 1Password prompt to let it fill in info, so clearly something was triggered.

I did not use the icon in Safari's toolbar. I never do, because I touch-type.