Watch the video:
Timestamps:
0:00 - Explanation
0:15 - Registry method does not work
0:28 - How to hide Insider Watermark
Using the Windows 10 or Windows 11 Insider builds, but annoyed by the watermark, even with a valid Windows key? Well, this video shows you how to turn off the annoying, unnecessary overlay. While it may help debug windows and things, most users will just be annoyed by its existence.
Winaero Universal Watermark Disabler article: https://winaero.com/download-universal-watermark-disabler/