Single instance Windows application helper in C#

SingleInstance.cs

/*
* Copyright (c) 2021 Pavel @ keenthinker.com
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), 
* to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, 
* and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

using System;
using System.Threading;
using System.Windows.Forms;

namespace Application
{
    /// <summary>
    /// Helper class that encapsulates the execution of an action only once at the first call.
    /// Subsequent calls of the same action will be ignored, as long as the first action call has not finished.
    /// </summary>
    public static class SingleInstance
    {
        /// <summary>
        /// Execute the first action once or execute the alternative action when the first is not yet finished.
        /// </summary>
        /// <param name="uniqueApplicationDescription">Unique name of the mutex. Name should be choosen carefully not to collide with other mutexes.</param>
        /// <param name="applicationTitle">Application title shown in the default message box.</param>
        /// <param name="oneInstanceAction">First action that is executed only once.</param>
        /// <param name="instanceNotUniqueAction">Action that is executed every time if the first action is still running.</param>
        public static void Start(string uniqueApplicationDescription, string applicationTitle, Action oneInstanceAction, Action instanceNotUniqueAction = null)
        {
            bool isFirstInstance = true;
            Mutex mutex = null;
            try
            {
                // if there is no custom second action, set a default one.
                if (instanceNotUniqueAction == null)
                {
                    instanceNotUniqueAction = () => MessageBox.Show("Application is already running!", applicationTitle, MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
                // 
                mutex = new Mutex(true, uniqueApplicationDescription, out isFirstInstance);
                if (isFirstInstance)
                {
                    oneInstanceAction();
                }
                else
                {
                    instanceNotUniqueAction();
                }
            }
            finally
            {
                if (isFirstInstance)
                {
                    if (mutex != null)
                    {
                        mutex.ReleaseMutex();
                    }
                }
            }
        }
    }
}

/*
/// <summary>
/// Example usage to create a single instance Windows application. 
/// The main entry point for the application.
/// </summary>
static void Main()
{
    SingleInstance.Start("Unique_String_for_example_a_GUID", "Application Title", () =>
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new ApplicationForm());
    });
}
*/