I’m hoping that macOS will eventually employ the use of the LG UltraFine Display’s built in ambient light sensor. However, if you like to use your MacBook Pro as a keyboard while connected to the LG UltraFine Display, then this tip might save you some time. If you’re using your MacBook Pro in clamshell mode with an external keyboard like the Magic Keyboard, then the built in keyboard shortcuts for brightness will do the job. On 10.12.4, brightness adjustments using the keyboard shortcut are nearly instant as one would expect them to be. However, with the latest macOS 10.12.4 beta, Apple has implemented a fix. I’ve noticed that in previous versions of macOS, employing this shortcut would result in a delay between key presses and the resulting brightness adjustments on the external display. A fix for delayed brightness adjustments in 10.12.4 beta Unfortunately, you can’t use the brightness slider while holding Control to adjust the external display just yet. By holding Control, you’ll notice the brightness change on your LG UltraFine Display instead of the MacBook Pro’s internal display. Step 2: Hold the Control (⌃) key on your MacBook Pro’s keyboard, and tap the brightness up or brightness down button. Step 1: Tap the chevron button on the Touch Bar to open the extended Control Strip to reveal the two brightness buttons. Subscribe to 9to5Mac on YouTube for more hands-on videos

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