The demos and examples for storing and retrieving GRID state uses the JavaScript localStorage.setItem and localStorage.getItem that work great.  As part of .NET 5 there's a Microsoft equivalent for accessing Local Storage using Microsoft.AspNetCore.Components.Server.ProtectedBrowserStorage.  I've found the behavior of these demos and examples will not work by simply replacing the JavaScript with .NET equivalents.  My experience is getting Circuit Handler exceptions that make these example not work.  

Although not a requirement since there's a JavaScript solution for local storage, I would like to recommend that since you partner closely with .NET team at Microsoft.  That your GRID development team test and provide examples with the Microsoft .NET 5 out-of-the-box local storage solution and resolve any incompatibilities for developers not wanting to use 1st party local storage solutions embedded within Microsoft Blazor.

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ADMIN EDIT

I made a sample test and things seemed to work for me, so I made a public example, you can find it in this pull request until it gets merged. I'm also attaching it to this post, but for anyone seeing this after a time - the public repository linked above is a better place to look for this in case more updates and information have been added since the time of writing this.

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