Top 20 NuGet alert Packages

Notify user when a new version of your app is available.
OXOX Design Modal
This app will alert you if a value on an incoming event does not match the predefined whitelist
A Razor Class Library that provides a means to display Flash Messages in an ASP.NET Core 3.1 web application. (Razor Pages and MVC are supported.) It depends on and utilizes Twitter Bootstrap for the alert CSS and HTML.
Toast alert notification for desktop