The update also fixed another problem. In the Systems Preferences->Security & Privacy ->General window, an ‘Allow’ button may appear if you need to give permission for unauthorized kernel extensions to load. In the original version of MacOS 10.13.6, clicking the button did nothing. However, after the update, clicking the button provides a list of developers for the unauthorized extensions. To authorize one, you click the check box next to the appropriate developer. Restarting the computer allows the extension to load. I needed to do this to install TripMode (https://tidbits.com/2015/07/22/tripmode-prevents-unwanted-internet-data-usage-on-a-tethered-mac/) on my new MacBook Pro.