docs: function isUnsupportedBrowser(minVersions, strictMode, ua) {
      var _bowser = bowser;
  
      // make strictMode param optional with ua param usage
      if (typeof strictMode === 'string') {
        ua = strictMode;
        strictMode = void(0);
      }
  
      if (strictMode === void(0)) {
        strictMode = false;
      }
      if (ua) {
        _bowser = detect(ua);
      }
  
      var version = "" + _bowser.version;
      for (var browser in minVersions) {
        if (minVersions.hasOwnProperty(browser)) {
          if (_bowser[browser]) {
            if (typeof minVersions[browser] !== 'string') {
              throw new Error('Browser version in the minVersion map should be a string: ' + browser + ': ' + String(minVersions));
            }
  
            // browser version and min supported version.
            return compareVersions([version, minVersions[browser]]) < 0;
          }
        }
      }
  
      return strictMode; // not found
    }