JAVASCRIPT

version check

navigator.sayswho= (function(){
    var ua= navigator.userAgent, tem, 
    M= ua.match(/(opera|chrome|safari|firefox|brave|msie|trident(?=/))/?s*(d+)/i) || [];
    if(/trident/i.test(M[1])){
        tem=  /rv[ :]+(d+)/g.exec(ua) || [];
        return 'IE '+(tem[1] || '');
    }
    if(M[1]=== 'Chrome'){
        tem= ua.match(/(OPR|Edge)/(d+)/);
        if(tem!= null) return tem.slice(1).join(' ').replace('OPR', 'Opera');
    }
    M= M[2]? [M[1], M[2]]: [navigator.appName, navigator.appVersion, '-?'];
    if((tem= ua.match(/version/(d+)/i))!= null) M.splice(1, 1, tem[1]);
    return M.join(' ');
})();

console.log(navigator.sayswho); // outputs: `Chrome 62`