rem: isPreferred: function(contentType, command, windowTarget, desiredContentType) 
add: isPreferred: function(contentType, command, desiredContentType) 
context:     isPreferred: function(contentType, command,                          windowTarget, desiredContentType)    {        // seems like we should be getting this from helper apps or something        switch(contentType) {            case "text/html":            case "text/xul":            case "text/rdf":            case "text/xml":            case "text/css":            case "image/gif":            case "image/jpeg":            case "image/png":            case "image/tiff":            case "text/plain":            case "application/http-index-format":                return true;        }        return false;    },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/13a0b3fbac64d68bf2529044bfa7439d05f5db0d/nsBrowserContentListener.js/buggy/suite/browser/nsBrowserContentListener.js