The document suggests that, if the firewall cannot be turned on, the user run the McAfee Virtual Technician. However, this does not seem to start using either Chrome or Safari on MacOS. Although not disclosed in the document mentioned previously or on the MVT page, I read in this community that MVT is not available for Mac.

How to Allow Apps to Communicate Through Your Mac’s Firewall Apr 07, 2016 Remove APPLE SECURITY BREACH (updated Jul 2020) - Removal Jul 01, 2020

Use Apple Remote Desktop with Macs behind firewalls - Mac

Apr 27, 2020

Is the built in firewall good enough to t… - Apple Community

McAfee Firewall Mac - McAfee Support Community Click the lock again, close the Firewall window, and then close Internet Security for Mac. I have version 3.x. Click the McAfee menulet in the menu bar (at the top of the screen near the clock) and select Preferences. Click on the Network Connections tab under the Firewall menu. Click the lock and type your administrator password if prompted. macos - Firewall for outgoing connections - Ask Different What you are referring to as "the built-in" firewall is actually the built-in Application Firewall. There two other built-in firewalls in OS X Lion, pf and ipfw (the latter is being replaced by pf, but still exist in Mountain Lion). These can handle both incoming and outgoing connections and are typically controlled through command line scripts