code: function expandMouseDownListener (e) { // For icon (UI.icons.originalIconBase + 'tbl-expand-trans.png')
      var target = thisOutline.targetOf(e)
      var p = target.parentNode
      var subject = UI.utils.getAbout(kb, target)
      var pane = e.altKey ? panes.internalPane : undefined // set later: was panes.defaultPane
  
      if (e.shiftKey) { // Shift forces a refocus - bring this to the top
        outlineRefocus(p, subject, pane)
      } else {
        if (e.altKey) { // To investigate screw ups, dont wait show internals
          outlineExpand(p, subject, {
            'pane': panes.internalPane,
            'immediate': true
          })
        } else {
          outlineExpand(p, subject)
        }
      }
    }
docs: things to do onmousedown in outline view * /*
  *   To Do:  This big event handler needs to be replaced by lots
  * of little ones individually connected to each icon.  This horrible
  * switch below isn't modular. (Sorry!) - Tim
   expand collapse refocus select visit/open a page