Accessing a Document being edited in a Outlook reading pane

Question

I have written a simple VSTO addon that inserts a hyperlink into an e-mail when user clicks on a ribbon bar button. Here is a code sample:

    private void button1_Click(object sender, RibbonControlEventArgs e)
    {
        var context = e.Control.Context as Inspector;

        if (context != null)
        {
            if (context.IsWordMail())
            {
                var doc = context.WordEditor as Document;
                if (doc != null)
                {
                    var sel = doc.Windows[1].Selection;
                    doc.Hyperlinks.Add(sel.Range, "http://www.google.com", "", "", "Google", "");
                }
            }
        }
        else if (e.Control.Context is Explorer)
        {
            Explorer explorer = Globals.ThisAddIn.Application.ActiveExplorer();

            if (explorer.Selection.Count == 1)
            {
                Microsoft.Office.Interop.Outlook.Selection itemSelection = explorer.Selection;
                var item = itemSelection[1] as MailItem;

                // get the instance of WordEditor in a reading pane?

            }
        }
    }

This works well when the e-mail is being edited in a separate windows (e.Control.Context is Inspector).

If the messsage is being replied to/forwarded and the reading pane is turned on, the editor is displayed inline in the reading pane (e.Control.Context is Explorer).

I can not figure out how to get the instance of the Document in this case. I can access the item selected in the Explorer but I cannot figure how to access the Document editor being displayed in a reading pane.

If I 'pop out' the editor to a separate window, it works fine (context changes to Inspector).

Is there a way to access a e-mail document which is edited directly inside reading pane?

---

With great help from Dmitry who pointed me in right direction I found out that there is a property in a Explorer class: Explorer.ActiveInlineResponseWordEditor which gives you editor displayed inline.