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Describe the bug
When using the keyboard to control brightness, the external monitor doesn’t respond. However, when adjusting brightness by dragging the slider in Control Center with the mouse, the external monitor’s brightness does change accordingly.
Steps to reproduce
- Click Volumn Up
- Built-in display brightness changes
- External display brightness does not change
Expected behavior
The external display brightness should change synchronously.
Anything else?
No response
Environment Information (please complete the following information)
- macOS version: MacOS 26.2
- Mac model: MacBook Air(13-inch,2025)
- MonitorControl version: v4.3.3
- Monitor(s): AOC U27U3XD
- Apple Silicon/M1 (yes or no): yes