if (!this.GM_getValue || (this.GM_getValue.toString && this.GM_getValue.toString().indexOf("not supported")>-1)) {
       this.GM_getValue=function (key,def) {
           return localStorage[key] || def;
       };
       this.GM_setValue=function (key,value) {
           return localStorage[key]=value;
       };
       this.GM_deleteValue=function (key) {
           return delete localStorage[key];
       };
}