MajorGeeks published a tutorial about how to delete the desktop wallpaper history in Windows 10.

How to Delete the Desktop Wallpaper History in Windows 10

When you change your Windows 10 background or wallpaper, you can choose from five images. Windows 10 does not include a way to clear the history of the last five images. Here's a workaround to clear the history.

How to Delete the Desktop Wallpaper History in Windows 10 - MajorGeeks