Are you on the latest version of the TinyMCE package. I can confirm on my instance that on 

  <package id="EPiServer.CMS" version="11.20.4" targetFramework="net472" />
  <package id="EPiServer.CMS.AspNet" version="11.20.4" targetFramework="net472" />
  <package id="EPiServer.CMS.Core" version="11.20.4" targetFramework="net472" />
  <package id="EPiServer.CMS.TinyMce" version="2.13.2" targetFramework="net472" />
  <package id="EPiServer.CMS.UI" version="11.32.1" targetFramework="net472" />
  <package id="EPiServer.CMS.UI.Core" version="11.32.1" targetFramework="net472" />

With the following TinyMCE module 

    /// <summary>
    /// Configures the settings for the TinyMCE editor in the episerver editor
    /// </summary>
    /// <seealso cref="EPiServer.ServiceLocation.IConfigurableModule" />
    [ModuleDependency(typeof(TinyMceInitialization))]
    public class ExtendedTinyMceInitialization : IConfigurableModule
    {
        /// <summary>
        /// Initializes this instance.
        /// </summary>
        /// <param name="context">The context.</param>
        /// <remarks>
        /// Gets called as part of the EPiServer Framework initialization sequence. Note that it will be called
        /// only once per AppDomain, unless the method throws an exception. If an exception is thrown, the initialization
        /// method will be called repeadetly for each request reaching the site until the method succeeds.
        /// </remarks>
        public void Initialize(InitializationEngine context)
        {
        }

        /// <summary>
        /// Resets the module into an uninitialized state.
        /// </summary>
        /// <param name="context">The context.</param>
        /// <remarks>
        /// <para>
        /// This method is usually not called when running under a web application since the web app may be shut down very
        /// abruptly, but your module should still implement it properly since it will make integration and unit testing
        /// much simpler.
        /// </para>
        /// <para>
        /// Any work done by <see cref="M:EPiServer.Framework.IInitializableModule.Initialize(EPiServer.Framework.Initialization.InitializationEngine)" /> as well as any code executing on <see cref="E:EPiServer.Framework.Initialization.InitializationEngine.InitComplete" /> should be reversed.
        /// </para>
        /// </remarks>
        public void Uninitialize(InitializationEngine context)
        {
        }

        /// <summary>
        /// Configure the IoC container before initialization.
        /// </summary>
        /// <param name="context">The context on which the container can be accessed.</param>
        public void ConfigureContainer(ServiceConfigurationContext context)
        {
            context.Services.Configure<TinyMceConfiguration>(config =>
            {
                config.Default()
                    .ContentCss("/Assets/Editor/editorstyles.css")
                    .AddPlugin("code wordcount media table") // code plugin to view the source html of editor
                    .Toolbar(
                        "epi-link image epi-image-editor media epi-personalized-content | cut copy paste pastetext | fullscreen code | help",
                        "blockquote alignleft aligncenter alignright alignjustify bold italic underline | bullist numlist | styleselect | undo redo searchreplace | table", 
                        "")
                    .StyleFormats(
                        new { title = "-- Text Styles --" },
                        new {title = "Standard Text", block = "p"},
                        new { title = "Header 1", block = "h1" },
                        new { title = "Header 2", block = "h2" },
                        new { title = "Header 3", block = "h3" },
                        new { title = "Header 4", block = "h4" }
                    );
            });
        }
    }

I am seeing the correct behaviour with the expected screen

HI Scott

I have upgarde the Tiny MCE version as well as our site version - but that does not seem to have made any difference.

We have tried with you configuration and with the one we have with no effect.

Any furhter input is much appreciated.

Thanks

Kind Regards

Sandeep

At a guess I would suggest trying to go through any other init modules, any display templates or custom editor definitions you may have in your site code and try investigating/disabling them. If the standard functionallity isn't working you may have something that's overriding the dojo editor such as a module config, display template or something like that as if you're using the code as show there shouldn't be a reason it doesn't work. Also maybe review any third party plugins you have too

Simply change from link to epi-link on this line in your configuration.

"outdent indent blockquote | undo redo | link unlink anchor image media pagebreak | insertdatetime preview | forecolor backcolor code",