rem: attachmentBox.hidden = false; document.getElementById("attachmentbucket-sizer").hidden=false; 
add:  var attachmentBox = document.getElementById("attachments-box"); if (attachmentBox.hidden) { attachmentBox.hidden = false; document.getElementById("attachmentbucket-sizer").hidden=false; } 
context:   onDragOver: function (aEvent, aFlavour, aDragSession)    {      // make sure the attachment box is visible during drag over      var attachmentBox = document.getElementById("attachments-box");      if (attachmentBox.hidden)      {        attachmentBox.hidden = false;        document.getElementById("attachmentbucket-sizer").hidden=false;      }    },
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/01692f0bbefbc59a2328dc795490a897f502ec20/MsgComposeCommands.js/buggy/mail/components/compose/content/MsgComposeCommands.js