Open the Firefox browser. Click on the menu button (three horizontal lines). Click on Add-ons and Themes. Search for Firefox Multi-account in Find more add-ons search bar. Select Firefox Multi-account Containers by Firefox. Firefox VPN is NOT an authorized application for MSU Denver devices. Select Add to Firefox button. Firefox VPN is NOT an authorized application for MSU Denver devices. Select Add in the permission access pop-up window. Firefox VPN is NOT an authorized application for MSU Denver devices.