rem: this.dialogElement( field ).setAttribute( "style", "display: none;" );  this.dialogElement( field+"Separator" ).setAttribute( "style", "display: none;" ); 
add: this.dialogElement( field ).hidden = true;   var sep = this.dialogElement( field+"Separator" ); if (sep) sep.hidden = true; 
context:     hide: function( field ) {        this.dialogElement( field ).setAttribute( "style", "display: none;" );        // Hide the associated separator, too.        this.dialogElement( field+"Separator" ).setAttribute( "style", "display: none;" );    },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/b86829b878a9fe8971faa3454ae417acac9586d1/nsProgressDialog.js/buggy/embedding/components/ui/progressDlg/nsProgressDialog.js