My Remote Desktop window shows in the middle of a black box when using Mission Control to send the full screen app from my MacBook Pro's Retina display to my Alienware screen
1. Change input on Alienware AW2521HFL from the PC host (DP) to the MacBook (HDMI) while Windows is still running
2. On the MacBook's Display preferences, turn off mirroring for the Alienware display
3. Open Remote Desktop Beta and connect to the PC using menu bar window
4. The Remote PC shows full screen on the default display, my MacBook's retina display
5. Swipe up with 4 fingers to show mission control and drag the Remote Desktop window to the left to the Alienware display
The desktop shows with a good portion of the window blacked out, with the remote computer showing in a low quality in the middle of the display
I have Remote Desktop set to display on a single screen at resolution: default for this display on my MacBook.
Workaround: Close the Remote Desktop window and re-open the session from the menu bar on the Alienware display.
macOS 12.3 Beta (21E5196i). MacBook Pro (13-inch, 2017, Four Thunderbolt 3 Ports)
Windows 11 Pro 21H2 22000.469 on an HP Omen 30L AMD Ryzen 7 58000X 3.8GHz
Remote Desktop Beta Client for macOS 10.7.5 (1969)