Hi,
The issue is caused by RadToastNotificationManager component and its dependency to Microsoft.Toolkit.Uwp.Notifications 6.1.1 which requires .NET Framework 4.6.1. We will remove the toast notification manager and the Microsoft.Toolkit.Uwp.Notifications 6.1.1 dependency from this package.
Still RadToastNotificationManager can be installed separately from the UI.for.WinForms.RadToastNotification NuGet.
Regards,
Hristo
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