rem: emailAddressNode.setAttribute("label", fullAddress); 
add: emailAddressNode.setAttribute("label", fullAddress || displayName); 
context: function updateEmailAddressNode(emailAddressNode, emailAddress, fullAddress, displayName, useShortView){  if (useShortView && displayName) {    emailAddressNode.setAttribute("label", displayName);    emailAddressNode.setAttribute("tooltiptext", emailAddress);  } else {    emailAddressNode.setAttribute("label", fullAddress);    emailAddressNode.removeAttribute("tooltiptext");  }  emailAddressNode.setTextAttribute("emailAddress", emailAddress);  emailAddressNode.setTextAttribute("fullAddress", fullAddress);    emailAddressNode.setTextAttribute("displayName", displayName);      if ("AddExtraAddressProcessing" in this)    AddExtraAddressProcessing(emailAddress, emailAddressNode);}
meta: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/82195fa8c999420412cdfc48c7d3b302bbd63a8e/msgHdrViewOverlay.js/clean/mailnews/base/resources/content/msgHdrViewOverlay.js