DocHub lets you import your Google Contacts for quick autofill of email addresses for your saved contacts. Once imported, you'll see typeahead suggestions for quick selection and entry in any email address field in DocHub.
Just click on the Address Book icon to the left of any email address field to import your contacts and choose your Google account in the window that comes up and allow access.
Once imported, just start typing in the field (at least 3 characters), and you'll see suggestions begin to populate in a drop-down menu below it for your saved contacts.
