Go to OSX Daily to read Adjust External Display Brightness on Mac with MonitorControl
Have you ever wished the keyboard brightness adjustment keys on a Mac could control the brightness of your external displays? Ever wanted to change the brightness on a secondary display, right from your Mac?
For users with multi-monitor setups, controlling brightness on multiple screens can be a chore when you have to manually fiddle with physical buttons on the external displays.
Fortunately with the help of a free third party utility called MonitorControl, you can easily set and adjust the display brightness of your external screens with the same brightness…
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