Make Windows 10 monochrome connection screen
Set the spot color as the Windows 10
(16) background in the taskbar and click the result to open the registry editor.
Navigate to the next registry key:
HKEY_LOCAL_MACHINESoftwarePoliciesMicrosoftWindowsSystem
Right-click in the empty field and select New > DWORD (32-bit) from the context menu, name it DisableLogonBackgroundImage and give it a value(17).
This will delete the default connection image and force Windows 10 to take the accent color of your desktop background.
To select your own color, open Settings > Customize > Colors and turn the slider to the Off position to Automatically select an accent color on my desktop.
