This [official Microsoft page](https://learn.microsoft.com/en-us/aspnet/core/client-side/spa-services?view=aspnetcore-3.0) says `Microsoft.AspNetCore.SpaServices` and `Microsoft.AspNetCore.NodeServices` are obsolete and "A simpler SPA frameworks integration mechanism is available" in `Microsoft.AspNetCore.SpaServices.Extensions`.

I can't find any documentation at all for `Microsoft.AspNetCore.SpaServices.Extensions`. There doesn't seem to be a corresponding namespace so I can't even find anything using IntelliSense.

The [obsolescence announcement on GitHub](https://github.com/aspnet/AspNetCore/issues/12890) is similarly vague.

Specifically, I'm trying to find out how to upgrade a call to `app.UseWebpackDevMiddleware`.

Where is the official documentation for `Microsoft.AspNetCore.SpaServices.Extensions`?