OnAppendCookie callback doesn't work

Nnobody.cs11/3/2022
I have an ASP.NET Core project, which uses IdentityServer4. In my configuration I have CookiePolicyOptions which contains the next setup:

services.Configure<CookiePolicyOptions>(
    option =>
    {
        option.MinimumSameSitePolicy = SameSiteMode.None;
        option.HttpOnly = Microsoft.AspNetCore.CookiePolicy.HttpOnlyPolicy.Always;
        option.OnAppendCookie = cookieContext =>
        {
            Console.WriteLine("Cookie appended: " + cookieContext.CookieName);
        };
        option.OnDeleteCookie = context =>
        {
            Console.WriteLine("Cookie deleted: " + context.CookieName);
        };
    });


For some reason, I can't reach the code from the OnAppendCooie and OnDeleteCookie.
I've also added a custom filter to append a new cookie to the response. The behavior was still the same - OnAppendCookie and OnDeleteCookie were not called.
Nnobody.cs11/3/2022
My filter looks like this
public class MyCustomFilter : ResultFilterAttribute
{
    public override void OnResultExecuting(ResultExecutingContext context)
    {
        context.HttpContext.Response.Cookies.Append("MyCustomCookie", "Blah-Blah");
        base.OnResultExecuting(context);
    }
}

and registration
services.AddControllersWithViews(c =>
{
    c.Filters.Add(new MyCustomFilter());
});
Image
Nnobody.cs11/3/2022
Am I missing something? I thought it should trigger when every cookie appends
Nnobody.cs11/3/2022
Nnobody.cs11/3/2022
Alright, I found the reason.
It requires an additional middleware.
app.UseCookiePolicy();
Nnobody.cs11/3/2022
:catfacepalm: