Don't like Sign-in screen blur on Windows 10? Here's how to disable it.

[Windows Central]

If you don't like the translucent texture in the background of the Sign-in screen, use this guide to disable it.
Starting with the Windows 10 May 2019 Update (version 1903), as part of the Fluent Design System gradual rollout, the Sign-in screen adds an acrylic effect that blurs the background, removing surrounding clutter and helping you to focus the attention in the login task.
While this is a welcome addition, it's not a feature for everyone. If you prefer the traditional experience with a clear background, you can disable the acrylic material effect from the Sign-in screen in at least three ways using the Settings app, Group Policy Editor, and the Registry.

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