Hello @Aeddon K. Evans
Thank you for reaching out to the Microsoft Q&A platform.
Yes, you are correct that the Windows App for Remote Desktop is currently only available through the Microsoft Store. However, Microsoft has stated that they are working on making the Windows App available through other channels, such as a traditional Windows installer. In the meantime, if your thin clients do not have access to the Microsoft Store, you can still use the existing Remote Desktop client to connect to Azure Virtual Desktop. Microsoft has stated that they will continue to support the existing Remote Desktop client until September 2024, so you have some time to plan for the transition to the Windows App.
If you would like to test the Windows App for Remote Desktop, you can try installing it on a different machine that has access to the Microsoft Store. Keep in mind that the Windows App is still in preview, so it may not be suitable for production use at this time.
https://techcommunity.microsoft.com/t5/windows-it-pro-blog/windows-app-general-availability-coming-soon/ba-p/4206647
Here is the statement from the windows app product team on the above announcement blog post
we will offer a direct download link of an MSIX package soon that will not be dependent on the Microsoft Store. It will be available on What's new in Windows App - Windows App | Microsoft Learn similar to the Remote Desktop client for Windows.
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