Mozilla/mozilla/mail/base/content/mailNavigatorOverlay.xul

<?xml version="1.0"?>

<!-- retrieve generic commands -->
<?xul-overlay href="chrome://messenger/content/mailOverlay.xul"?>

<!DOCTYPE window SYSTEM "chrome://messenger/locale/mailNavigatorOverlay.dtd" >

<overlay id="mailNavigatorOverlay"
         xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">

  <script type="application/x-javascript">
  <![CDATA[
    function getCurrentIdentityKey()
    {
      try 
      {
        var cwindowManager = Components.classes['@mozilla.org/appshell/window-mediator;1'].getService();
        var iwindowManager = Components.interfaces.nsIWindowMediator;
        var windowManager  = cwindowManager.QueryInterface(iwindowManager);
        var mailWindow = windowManager.getMostRecentWindow('mail:3pane');
        var folder = mailWindow.GetFirstSelectedMsgFolder();
        var server = folder.server;
        if (server.type == "nntp")//if the account is a news account use default identity
          return null;
        else {
          var identity = mailWindow.getIdentityForServer(server);
          return identity;
        }
      }
      catch(ex) {
        return null;
      }
    }

    // attachment: 0 - link
    //             1 - page
    //             2 - image
    function openComposeWindow(url, title, attachment)
    {                                                                          
      var params = Components.classes["@mozilla.org/messengercompose/composeparams;1"].createInstance(Components.interfaces.nsIMsgComposeParams);
      if (params)
      {
        params.composeFields = Components.classes['@mozilla.org/messengercompose/composefields;1'].createInstance(Components.interfaces.nsIMsgCompFields);
        if (params.composeFields)
        {
          if (attachment == 0 || attachment == 1)
          {
            params.composeFields.body = url;
            params.composeFields.subject = title;
            params.bodyIsLink = true;
          }
          if (attachment == 1 || attachment == 2)
          {
            var attachmentData = Components.classes["@mozilla.org/messengercompose/attachment;1"].createInstance(Components.interfaces.nsIMsgAttachment);
            if (attachmentData)
            {
              attachmentData.url = url;
              params.composeFields.addAttachment(attachmentData);
            }
          }
          params.identity = getCurrentIdentityKey();
          var composeService = Components.classes["@mozilla.org/messengercompose;1"].getService(Components.interfaces.nsIMsgComposeService);
          if (composeService)
            composeService.OpenComposeWindowWithParams(null, params);
        }                                                                         
      }                                                                         
    }   
  
    function sendLink(pageUrl, pageTitle)
    {
      try {
        openComposeWindow(pageUrl, pageTitle, 0);
      } catch(ex) { dump("Cannot Send Link: " + ex + "\n"); }
    }

    function sendImage(imageURL)
    {
      try {
        openComposeWindow(imageURL, null, 2);
      } catch(ex) { dump("Cannot Send Image: " + ex + "\n"); }
    }

    function sendPage(aDocument)
    {
      if (!aDocument)
        aDocument = window._content.document;
        
      var pageUrl = aDocument.URL;
      var pageTitle = Components.lookupMethod(aDocument, 'title').call(aDocument);

      try {
        openComposeWindow(pageUrl, pageTitle, 1);
      } catch(ex) { dump("Cannot Send Page: " + ex + "\n"); }
    }

    function initMailContextMenuItems(aEvent)
    {
      var shouldShowSendPage = !(gContextMenu.onTextInput || gContextMenu.isTextSelected) && !(gContextMenu.onLink && gContextMenu.onImage);
      gContextMenu.showItem("context-sendpage", shouldShowSendPage);
   
      gContextMenu.showItem("context-sep-apps", gContextMenu.shouldShowSeparator("context-sep-apps"));
    }
      
    var gAddedMailContextMenuPopupListener = false;
    function initMailContextMenuPopupListener(aEvent)
    {
      // This is really lame, but we can't seem to add a bubbling listener to the DOMWindow (!)
      if (gAddedMailContextMenuPopupListener)
        return;
      var popup = document.getElementById("contentAreaContextMenu");
      popup.addEventListener("popupshowing", initMailContextMenuItems, false);
      gAddedMailContextMenuPopupListener = true;
    }

    addEventListener("load", initMailContextMenuPopupListener, true);
  ]]>
  </script>         

  <!-- navigator specific commands -->
  <commandset id="tasksCommands">
    <command id="cmd_sendPage" oncommand="sendPage();"/>
    <command id="Browser:SendLink"
             oncommand="sendLink(Components.lookupMethod(window._content, 'location').call(window._content).href,
                                 Components.lookupMethod(window._content.document, 'title').call(window._content.document));"/>
  </commandset>
         
  <!-- navigator specific UI items -->
  <menupopup id="menu_NewPopup">
    <menuitem id="menu_newCard" insertafter="navBeginGlobalNewItems"/>
    <menuitem id="menu_newMessage" insertafter="navBeginGlobalNewItems"/>
  </menupopup>

  <menupopup id="menu_FilePopup">
    <menuitem id="menu_sendPage" label="&sendPage.label;" accesskey="&sendPage.accesskey;" command="cmd_sendPage" position="9"/>
    <menuitem id="menu_sendLink" label="&sendLinkCmd.label;" accesskey="&sendLinkCmd.accesskey;" command="Browser:SendLink" position="10"/>
  </menupopup>

  <popup id="contentAreaContextMenu">
    <menuitem id="context-sendpage"
              label="&contextSendPage.label;"
              accesskey="&contextSendPage.accesskey;"
              oncommand="sendPage();"
              insertafter="context-savepage"/>
    <menuitem id="context-sendimage"
              label="&contextSendImage.label;"
              accesskey="&contextSendImage.accesskey;"
              oncommand="sendImage(gContextMenu.imageURL);"
              insertafter="context-saveimage"/>
    <menu id="frame">
    <menupopup id="frame_popup">
      <menuitem insertafter="saveframeas"
                label="&contextSendFrame.label;"
                accesskey="&contextSendFrame.accesskey;"
                oncommand="sendPage(gContextMenu.target.ownerDocument);"/>
    </menupopup>
    </menu>
  </popup> 
  
</overlay>