Auto-fill appears to identify the message field in the form as a zip code field. I am manually going to turn auto-complete off for that input on my end today, however, I am hoping that this can be incorporated directly at the developer level so that I don’t have to redo it each time the plugin updates.

Another idea: incorporate a checkbox into the settings pane to give plugin users the ability to choose whether they would like auto-complete to be on/off for each field.