Mac OS X 10.12.3: Reconnecting UltraFine 5K monitor makes desktop background black sometimes

Originator:avedesk
Number:rdar://30681537 Date Originated:23-Feb-2017 10:17 PM
Status:Open Resolved:
Product:macOS Product Version:Mac OS X 10.12.3 (16D32)
Classification:UI/Usability Reproducible:Rarely
 
Summary:
When disconnecting and reconnecting a Thunderbolt 3 monitor (UltraFine 5K), sometimes the desktop background stays black, instead of showing the desktop picture.

Steps to Reproduce:
1. Attach an UltraFine 5K monitor to a MacBook Pro 2016 13" in clamshell mode
2. Set a colorful Desktop Picture
3. Disconnect monitor
4. Reconnect monitor
5. Perform steps 3 to 4 multiple times until the issue shows up

Expected Results:
- Desktop Picture is shown

Actual Results:
- A black background is shown instead of the Desktop Picture. Running `killall Dock` resolves the issue

Regression:

Notes:
Please find any sysdiagnose on any of my other UltraFine 5K related issues

Comments


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