hangfire_dashboard.cs

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseRouting();

            app.UseAuthorization();

            // ================>
            app.UseHangfireDashboard();

            // <================

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });
        }