var u = "Browser";
if (this.isIPad) {
u = "iPad"
} else {
if (this.isDDGIgnore) {
u = "Ignore"
} else {
if (/seamonkey/.test(x)) {
u = "SeaMonkey"
} else {
if (/iceape/.test(x)) {
u = "Iceape"
} else {
if (/palemoon/.test(x)) {
u = "PaleMoon"
} else {
if (this.isFirefox) {
u = "Firefox"
} else {
if (this.isAndroid) {
u = "Android"
} else {
if (/xbox/.test(x)) {
u = "xBox"
} else {
if (/midori/.test(x)) {
u = "Midori"
} else {
if (/opr/.test(x)) {
u = "Opera"
} else {
if (/maxthon/.test(x)) {
u = "Maxthon"
} else {
if (this.isYandex) {
u = "Yandex"
} else {
if (/vivaldi/.test(x)) {
u = "Vivaldi"
} else {
if (this.isChrome) {
u = "Chrome"
} else {
if (/fennec/.test(x)) {
u = "Fennec"
} else {
if (/epiphany/.test(x)) {
u = "Epiphany"
} else {
if (this.isFirefox) {
u = "Firefox"
} else {
if (/uzbl/.test(x)) {
u = "Uzbl"
} else {
if (this.isEdge) {
u = "Edge"
} else {
if (this.isIE && navigator.platform === "Win64" && !k() && Modernizr.touch && document.documentElement.clientWidth == screen.width) {
u = "IEMetro"
} else {
if (this.isIE) {
u = "IE"
} else {
if (this.isOpera) {
u = "Opera"
} else {
if (this.isIPhone) {
u = "iPhone"
} else {
if (/arora/.test(x)) {
u = "Arora"
} else {
if (this.isSafari) {
u = "Safari"
} else {
if (this.isKonqueror) {
u = "Konqueror"
} else {
if (this.isBlackberry) {
u = "Blackberry"
} else {
if (/phantomjs/.test(x)) {
u = "PhantomJS"
} else {
if (this.isIDevice) {
u = "iOS"
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
}
Found when looking at facebook.com code and formatting using google chrome developer tools.