rem: if ((navigator.platform.indexOf("Win") == -1) && (navigator.platform.indexOf("OS/2") == -1) && (navigator.platform.indexOf("Mac") == -1)) { document.getElementById("btn_openfile").hidden = true; } 
add: document.getElementById("btn_openfile").hidden = gCannotLaunch; document.getElementById("downloadPaneContext-openfile").hidden = gCannotLaunch; 
context: function DLManagerStartup(){    if (!window.arguments.length)    return;  try {    var observerService = Components.classes[kObserverServiceProgID]                                    .getService(Components.interfaces.nsIObserverService);    observerService.addObserver(dlObserver, "download-starting", false);  }  catch (ex) {  }  const rdfSvcContractID = "@mozilla.org/rdf/rdf-service;1";  const rdfSvcIID = Components.interfaces.nsIRDFService;  gRDFService = Components.classes[rdfSvcContractID].getService(rdfSvcIID);    gNC_File = gRDFService.GetResource(NC_NS + "File");  gDownloadView = document.getElementById("downloadView");  setSortVariables(gDownloadView);  const dlmgrContractID = "@mozilla.org/download-manager;1";  const dlmgrIID = Components.interfaces.nsIDownloadManager;  gDownloadManager = Components.classes[dlmgrContractID].getService(dlmgrIID);  const ioSvcContractID = "@mozilla.org/network/io-service;1";  const ioSvcIID = Components.interfaces.nsIIOService;  var ioService = Components.classes[ioSvcContractID].getService(ioSvcIID);  const fileHandlerIID = Components.interfaces.nsIFileProtocolHandler;  gFileHandler = ioService.getProtocolHandler("file")                          .QueryInterface(fileHandlerIID);  var ds = window.arguments[0];  gDownloadView.database.AddDataSource(ds);  gDownloadView.builder.rebuild();  window.setTimeout(onRebuild, 0);  var key;  if ((navigator.platform.indexOf("Win") == -1) &&      (navigator.platform.indexOf("OS/2") == -1) &&      (navigator.platform.indexOf("Mac") == -1))  {    document.getElementById("btn_openfile").hidden = true;  }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/e85bf9ab5efbf5fbfae1e62a0cdb5807b0c11a2c/downloadmanager.js/clean/xpfe/components/download-manager/resources/downloadmanager.js