NightShift hangs macOS with external display connected

Originator:m
Number:rdar://30281846 Date Originated:31-Jan-2017
Status:Closed Resolved:
Product:macOS + SDK Product Version:10.12.4
Classification:No Value Reproducible:Always
 
Matteo Gavagnin31-Jan-2017 09:49 AM

Summary:
If you enable Night Shift and connect a LG Ultrafine 4K monitor macOS freezes.

Steps to Reproduce:
1 - Enable Night Shift
2 - Connect external 4K monitor
3 - System hangs with spinning beach ball
4 - Disconnect external monitor
5 - Disable Night Shift
6 - Connect external monitor
7 - Everything works fine

Expected Results:
I do expect to be able to keep Night Shift enable even if I attach an external monitor.

Actual Results:
If you enable Night Shift and connect a LG Ultrafine 4K monitor macOS freezes.

Regression:
The problem occurs on 10.12.4 beta 1. Doesn't occur on previous macOS versions as they don't include Night Shift mode.

Notes:
Tested only with the LG Ultrafine 4K external monitor attached directly to the single USB-C port  on a 2016 MacBook 12" without any other peripheral connected.

Comments


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