add: viewMenu.setAttribute('disabled', true); 
context: function onShowAttachmentContextMenu(){  // if no attachments are selected, disable the Open and Save...  var attachmentList = document.getElementById('attachmentList');  var selectedAttachments = attachmentList.selectedItems;  var openMenu = document.getElementById('context-openAttachment');  var saveMenu = document.getElementById('context-saveAttachment');  var detachMenu = document.getElementById('context-detachAttachment');  var deleteMenu = document.getElementById('context-deleteAttachment');  var detachAllMenu = document.getElementById('context-detachAllAttachments');  var deleteAllMenu = document.getElementById('context-deleteAllAttachments');  var canDetach = CanDetachAttachments();  var canOpen = false;  for (var i = 0; i < selectedAttachments.length && !canOpen; i++)    canOpen = selectedAttachments[i].attachment.contentType != 'text/x-moz-deleted';  if (canOpen && selectedAttachments.length == 1)  {    openMenu.removeAttribute('disabled');  }  else  {    openMenu.setAttribute('disabled', true);  }  if (canOpen)  {    saveMenu.removeAttribute('disabled');  }  else  {    saveMenu.setAttribute('disabled', true);  }  if (canDetach && canOpen)  {    detachMenu.removeAttribute('disabled');    deleteMenu.removeAttribute('disabled');  }  else  {    detachMenu.setAttribute('disabled', 'true');    deleteMenu.setAttribute('disabled', 'true');  }  if (canDetach)  {    detachAllMenu.removeAttribute('disabled');    deleteAllMenu.removeAttribute('disabled');  }  else  {    detachAllMenu.setAttribute('disabled', 'true');    deleteAllMenu.setAttribute('disabled', 'true');  }}
meta: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/8395/5f5a9dd71ae4ad6dc00c4f9cf438579817dd4558/msgHdrViewOverlay.js/clean/mailnews/base/resources/content/msgHdrViewOverlay.js