Hi Justin Kent,
Thank you for posting in the Microsoft Community Forums.
Regarding enabling a dark mode theme in AD LDS, there may not be direct support or specific settings to achieve this purpose. AD LDS is a technology focused on providing lightweight directory services, and it does not offer user interface theme options like those found in desktop operating systems.
However, you can indirectly achieve the use of a dark mode theme in an AD LDS instance on Windows Server 2019 through the following methods:
Windows Server Theme: The user interface for AD LDS is typically based on the default theme of Windows Server. You can attempt to change the theme of Windows Server to dark mode, which will affect the entire operating system interface, including AD LDS management tools. To change the theme of Windows Server, you can right-click on the desktop and select "Personalize," then choose "Dark" under the "Colors" tab.
Best regards
Neuvi Jiang
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