Rui CarmoMonitorControl is an open source utility to control external monitor brightness, contrast or volume directly from a menulet or with keyboard native keys.
It leverages the DDC protocl and is written in Swift.
Resources
- Discussion on M1 support
- Lunar, an application that changes brightness and contrast automatically throughout the day.
- Twinkle Tray, a Windows application that offers similar functionality and has worked well for me with some LG monitors.