My External monitor shows only a black screen in Extended Display after updating to macOS Golden Gate Beta 27.0 (26A5368g)
I have a Mac with an M4 chip and 24 GB RAM connected to an external monitor. Everything was working perfectly before updating.
After installing macOS Golden Gate Beta 27.0 (26A5368g), my external monitor stopped working properly in Extended Display mode.
Here's what's happening:
- The external monitor turns on but only shows a black screen.
- I can see and move my mouse cursor on the external monitor.
- I can't move windows or switch Spaces/desktops to the external monitor anymore. It feels like the display isn't actually rendering a desktop even though the cursor is there.
- If I switch to Mirror Displays or make the external monitor my Main Display, everything works perfectly and the display is shown correctly. The issue only occurs when using the monitor as an Extended Display.
- Disconnecting and reconnecting the monitor doesn't help.
I've attached a screen recording demonstrating the issue. Here.
Has anyone else experienced this after installing the beta? Is this a known bug with macOS Golden Gate Beta, or is there a workaround?
Things I've tried (or am planning to try):
- Restarting the Mac
- Reconnecting the monitor/cable
- Detect Displays(by holding option key)
- Toggling Mirror/Extend mode
- Reinstalled macOs 27
- Resetting display preferences
Any suggestions or confirmation that this is a beta bug would be greatly appreciated. Thanks!
u/Medical_Resident_110 — 7 days ago