Microsoft Identity and OpenIdConnection

Question

I'm trying to connect my web application with .NET5 and the new Microsoft.AspNetCore.Authentication.OpenIdConnect. Apparently, my old code for OpenIdConnect is valid but it doesn't work. This is what I'm adding to the ConfigureServices:

services.AddSession(options =>
{
    options.Cookie.Name = ".puresourcecode.session";
    options.IdleTimeout = TimeSpan.FromHours(12);
});

services.AddAuthentication(options =>
{
    options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
    options.DefaultChallengeScheme = "oidc";
})
.AddCookie(options =>
{
    options.ExpireTimeSpan = TimeSpan.FromMinutes(30);
    options.Cookie.Name = "puresourcecode.cookie";
})
.AddOpenIdConnect("oidc", options =>
{
    options.Authority = idsrv.IdentityServerUrl;
    options.ClientId = idsrv.ClientId;
    options.ClientSecret = idsrv.ClientSecret;

#if DEBUG
        options.RequireHttpsMetadata = false;
#else
        options.RequireHttpsMetadata = true;
#endif

        options.ResponseType = "code";

    options.Scope.Clear();
    options.Scope.Add("openid");
    options.Scope.Add("profile");
    options.Scope.Add("email");
    options.Scope.Add("roles");
    options.Scope.Add("offline_access");

    options.ClaimActions.MapJsonKey("role", "role", "role");

    options.GetClaimsFromUserInfoEndpoint = true;
    options.SaveTokens = true;

    options.SignedOutRedirectUri = "/";

    options.TokenValidationParameters = new TokenValidationParameters
    {
        NameClaimType = JwtClaimTypes.Name,
        RoleClaimType = JwtClaimTypes.Role,
    };
});

and this is what I add to the Configure:

if (env.IsDevelopment())
{
    app.UseDeveloperExceptionPage();
}
else
{
    app.UseExceptionHandler("/Home/Error");
    app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();

app.UseRouting();

app.UseCookiePolicy();
app.UseAuthentication();
app.UseAuthorization();
app.UseSession();

app.UseEndpoints(endpoints =>
{
    endpoints.MapControllerRoute(
        name: "default",
        pattern: "{controller=Home}/{action=Index}/{id?}");
});

Then, 2 questions:

• is it possible to connect a .NET5 (ASP.NET) project to IdentityServer4?
• is it possible use Microsoft Identity and OpenIdConnect in the same project?