Why did Windows 7, for a few months, log on slower if you have a solid color background?
https://devblogs.microsoft.com/oldnewthing/20250428-00/?p=111121 [devblogs.microsoft.com]
2025-04-28 21:20
The code to report that the wallpaper is ready was inside the wallpaper bitmap code, which means that if you don’t have a wallpaper bitmap, the report is never made, and the logon system waits in vain for a report that will never arrive.