...
Set the default email app or web browser on your Mac
Install Google Notifier
Installing Google Notifier will change your default mail setting in all browsers (Chrome, Firefox and Internet Explorer), but it does require you to use your device password if you have enrolled in Duo Security.
In any browser, navigate to Google Notifier.
Choose the Notifier download file for your operating system (Windows or Mac).
During the install, choose a standard installation (defaults to "Use for outgoing mail").
You will be prompted for your username and password. Enter your full email address (name@drew.edu) and your password. If you have enrolled in the Duo Two-Factor Authentication service, use your Device Password instead.
The next time you click on an email link, you will be directed to Gmail.