Combobox functionality with the autoComplete (browser) attribute

[scarabcoder]

I'm attempting to build out an address form, with a Combobox component for the Country and State fields.
I find it very helpful to use the browser autocomplete attribute, which allows browsers that support it to suggest/autofill into those fields automatically.

When used with a Combobox, though, as soon as the user tries to autofill the form it opens up the Combobox dropdown, opening up multiple dropdowns on the same page for each field that is autofilled.
The ideal behavior is that it would automatically select the value from the dropdown list, but what actually happens is that it attempts to search for the value.

I'm wondering if this is even possible with how user autofill works, since it may not be possible to tell when it's a browser autofill event vs regular user input?