Step 1: On the Mac computer, navigate to the Certificate Portal of the firewall. This can be accessed by going to http://<IP of Interface>:4126/certportal
Step 2: Once you access the Certificate Portal, download the certificate that is available.
Step 3: Once the certificate downloads, double-click to open it. This will open the Keychain Access program on the Mac. Search for the certificate called Fireware HTTPS Proxy, and double-click on it.
Step 4: Expand the section that says Trust. Next to the option called When using this certificate, set to Always Trust.
Step 5: Close out of the Fireware HTTPS Proxy window. You will be prompted to enter the credentials of the logged in user. Once you do so, the certificate will be trusted on the device.