Hi Alexandre Ribeiro do Nascimento,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
I understand your concern as the random authentication causes issues, as users may not be authenticated with the correct partner's identity. To resolve this, users need to log out and try again, hoping to be authenticated with the correct identity.
The Azure Virtual Desktop (AVD) portal does not currently support identifying the tenant from the URL.
Microsoft Entra application proxy provides secure remote access to on-premises web applications. After a single sign-on to Microsoft Entra ID, users can access both cloud and on-premises applications through an external URL or an internal application portal. Even with this workaround, you still can't identify the tenant from the URL. Users would still need to sign in through the Azure portal using their Azure AD credentials.
If you want to learn more about accessing AVD resources: https://learn.microsoft.com/en-us/azure/virtual-desktop/users/connect-web#access-your-resources
If you have any further queries, do let us know.
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