Get platform and standalone mode

platform.js

isInStandaloneMode() {
    return (window.matchMedia("(display-mode: standalone)").matches) ||
        (("standalone" in window.navigator) && (window.navigator.standalone));
}
isMac() {
    return /(macintosh|macintel|macppc|mac68k|macos)/i.test(window.navigator.userAgent.toLowerCase());
}
isIos() {
    return /iphone|ipad|ipod/i.test(window.navigator.userAgent.toLowerCase());
}
platform() {
    let userAgent = window.navigator.userAgent.toLowerCase(),
        macosPlatforms = /(macintosh|macintel|macppc|mac68k|macos)/i,
        windowsPlatforms = /(win32|win64|windows|wince)/i,
        iosPlatforms = /(iphone|ipad|ipod)/i;

    if (macosPlatforms.test(userAgent)) {
        return "macos";
    }
    if (iosPlatforms.test(userAgent)) {
        return "ios";
    }
    if (windowsPlatforms.test(userAgent)) {
        return "windows";
    }
    if (/android/.test(userAgent)) {
        return "android";
    }
    if (/linux/.test(userAgent)) {
        return "linux";
    }

    return null;
}