Mintra url string replace, C#

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//Title of this code
//Rextester.Program.Main is the entry point for your code. Don't change it.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        
        private static readonly Regex configValueExtrator = new Regex(@"^((?:http|https)://[^\{]*)({id})(/startCourse)");
        private static readonly string config = "https://test.mintra.no/mintra/sso/directAccess/{id}/startCourse";
        private static readonly string enrollmentId = "f7848557-27da-4423-a44e-0a0adab93a08";
        public static void Main(string[] args)
        {
            var matches = configValueExtrator.Matches(config);
            var url = config.Replace("{id}", enrollmentId);
            Console.WriteLine("Url: {0}", url);

foreach(Match match in matches){
                Console.WriteLine("**MATCH**");
                Console.WriteLine(match.Value);
                foreach(Group grp in match.Groups){
                    Console.WriteLine("\t**GROUP**");
                    Console.WriteLine("\t{0}", grp.Value);
                    
                    foreach(Capture capture in grp.Captures){
                        Console.WriteLine("\t\t**Capture**");
                        Console.WriteLine("\t\t{0}", capture.Value);
                    }
                }
            }
        }
        
        private static bool _restrict = true;
        public static bool Restrict
        {
            get{ return _restrict;}
            private set { _restrict = value; }
        }

private static List<string> _validRecipients = new List<string>();
        public static IEnumerable<string> ValidRecipients
        {
            get { return _validRecipients; }
            private set { _validRecipients = value.ToList(); }
        }

public static void ParseConfigString(string config)
        {
            var matches = configValueExtrator.Matches(config);

if (matches.Count < 1)
            {
                return;
            }

var match = matches[0];
            if (match.Groups.Count < 3)
            {
                return;
            }

_restrict = !match.Groups[1].Value.Equals("false");

foreach (Capture capture in match.Groups[2].Captures)
            {
                _validRecipients.Add(capture.Value);
            }

}
        
    }
}

Show compiler warnings [ + ] Show input
Compilation time: 0.22 sec, absolute running time: 0.34 sec, cpu time: 0.33 sec, average memory usage: 19 Mb, average nr of threads: 5