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// Opera 8.0+
let isOpera =
(!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(" OPR/") >= 0;
// Firefox 1.0+
let isFirefox = typeof InstallTrigger !== "undefined";
// Safari 3.0+ "[object HTMLElementConstructor]"
let isSafari =
/constructor/i.test(window.HTMLElement) ||
(function(p) {
return p.toString() === "[object SafariRemoteNotification]";
})(!window["safari"] || (typeof safari !== "undefined" && safari.pushNotification));
// Internet Explorer 6-11
let isIE = /*@cc_on!@*/ false || !!document.documentMode;
// Edge 20+
let isEdge = !isIE && !!window.StyleMedia;
// Chrome 1+
let isChrome =
!isOpera && !isFirefox && !!navigator.userAgent.toLowerCase().match(/chrome/);
let supportDirectory = !!isFirefox || !!isChrome;
// Blink engine detection
let isBlink = (isChrome || isOpera) && !!window.CSS;
