With the launch of Windows 11, Microsoft adapted an entirely new user interface and theme design for the operating system. The operating system brought better dark mode integration system-wide and the company also started updating its first-party apps to match the entire new Fluidic design interface with rounded corners of the operating system. The Paint app has also been updated, however, dark mode was still missing despite the latest update. Finally, the company has started rolling out the dark mode for Paint to beta testers in Windows Insider. Which means, the feature could soon make its way to the stable version.

source https://www.gadgetsnow.com/apps/microsoft-starts-rolling-out-dark-mode-for-paint-to-these-windows-11-users-heres-how-you-can-get-it/articleshow/100775717.cms