Exception thrown when clicking empty line in Image History Detail

I have just tacked this on the end of another post but thought best to make a clean report.

It you pull up the Image History Detail and right-click on and empty line the exception below is thrown.

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
at SequenceGenerator.ImageHistoryTextDisplay.c(Object A_0, MouseEventArgs A_1)
at System.Windows.Forms.Control.OnMouseUp(MouseEventArgs e)
at System.Windows.Forms.ListView.WmReflectNotify(Message& m)
at System.Windows.Forms.ListView.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

************** Loaded Assemblies **************

Windows 8.1 x64

Thank you for the report. This issue has been fixed and will be released with the first 2.4.2 beta (soon).