Hello, 
 
A Fix will be available in LIB Version 2019.1.401 scheduled for April 1st.

Best regards, 
Dimitar

The workaround didn't work for a specific button. The button open's a third party software (.exe)

 

I tried calling a Refresh, also an Application.DoEvents but nothing is working. The other application is doing a file or folder browser dialog. 

 

private void radButtonConvert_Click(object sender, EventArgs e)
        {
            if (radRibbonBarMain.RibbonBarElement.Popup != null)
            {
                radRibbonBarMain.RibbonBarElement.Popup.ClosePopup(Telerik.WinControls.UI.RadPopupCloseReason.Mouse);
                Refresh();
                Application.DoEvents();
            }

            try
            {
                // Use ProcessStartInfo class
                ProcessStartInfo startInfo = new ProcessStartInfo();
                startInfo.CreateNoWindow = false;
                startInfo.UseShellExecute = false;
                startInfo.FileName = "ConfigurationConversion.exe";
                startInfo.WindowStyle = ProcessWindowStyle.Normal;
                startInfo.Verb = "runas";

                // Start the process with the info we specified.
                // Call WaitForExit and then the using statement will close.
                using (Process exeProcess = Process.Start(startInfo))
                {
                    exeProcess.WaitForExit();
                }
            }
            catch
            {
                // Log error.
            }
        }