How to use the bowser.gecko function in bowser

.then(() =>
					{
						// If Firefox trigger 'forcestreamsupdate' event due to bug:
						// https://bugzilla.mozilla.org/show_bug.cgi?id=1347578
						if (browser.firefox || browser.gecko)
						{
							// Not sure, but it thinks that the timeout does the trick.
							setTimeout(() => this.emit('forcestreamsupdate'), 500);
						}
					});

padSize: browser.ios ? 0 : 3,

  // In order to prevent fallback tiles from overlapping their children, iOS
  // requires smaller zoom levels to be placed below larger zoom levels in
  // the CSS 3D coordinate space.
  reverseLevelDepth: browser.ios,

  // A null transform on the layer element is required so that transitions
  // between layers work on iOS.
  useNullTransform: browser.ios,

  // On Webkit and Gecko browsers, some tiles become invisible at certain
  // angles, usually non-floor tiles when looking straight down. Setting the
  // translateZ following the perspective transform to a slightly larger value
  // than the latter seems to work around this glitch.
  perspectiveNudge: browser.webkit || browser.gecko ? 0.001 : 0

};


/**
 * @class CssStage
 * @extends Stage
 * @classdesc
 *
 * A {@link Stage} implementation using CSS 3D Transforms.
 *
 * @param {Object} opts
 *
 * Also see the available {@link Stage} options.
 */
function CssStage(opts) {

hasWebRTC = true;
		getUserMedia = virtNavigator.mozGetUserMedia.bind(virtNavigator);
		mediaDevices = virtNavigator.mediaDevices;
		RTCPeerConnection = virtGlobal.mozRTCPeerConnection;
		RTCSessionDescription = virtGlobal.mozRTCSessionDescription;
		RTCIceCandidate = virtGlobal.mozRTCIceCandidate;
		MediaStreamTrack = virtGlobal.MediaStreamTrack;
		attachMediaStream = function (element, stream) {
			element.src = URL.createObjectURL(stream);
			return element;
		};
		canRenegotiate = false;
		oldSpecRTCOfferOptions = false;
	// Modern Firefox desktop, modern Firefox Android.
	} else if (
		((browser.firefox || browser.gecko) && browserVersion >= 47)
	) {
		hasWebRTC = true;
		getUserMedia = virtNavigator.mozGetUserMedia.bind(virtNavigator);
		mediaDevices = virtNavigator.mediaDevices;
		RTCPeerConnection = virtGlobal.RTCPeerConnection;
		RTCSessionDescription = virtGlobal.RTCSessionDescription;
		RTCIceCandidate = virtGlobal.RTCIceCandidate;
		MediaStreamTrack = virtGlobal.MediaStreamTrack;
		attachMediaStream = function (element, stream) {
			element.src = URL.createObjectURL(stream);
			return element;
		};
		canRenegotiate = false;
		oldSpecRTCOfferOptions = false;
		// WebRTC plugin required. For example IE or Safari with the Temasys plugin.
	} else if (

hasWebRTC = true;
		getUserMedia = virtNavigator.mozGetUserMedia.bind(virtNavigator);
		mediaDevices = virtNavigator.mediaDevices;
		RTCPeerConnection = virtGlobal.mozRTCPeerConnection;
		RTCSessionDescription = virtGlobal.mozRTCSessionDescription;
		RTCIceCandidate = virtGlobal.mozRTCIceCandidate;
		MediaStreamTrack = virtGlobal.MediaStreamTrack;
		attachMediaStream = function (element, stream) {
			element.src = URL.createObjectURL(stream);
			return element;
		};
		canRenegotiate = false;
		oldSpecRTCOfferOptions = false;
	// Modern Firefox desktop, modern Firefox Android.
	} else if (
		((browser.firefox || browser.gecko) && browserVersion >= 47)
	) {
		hasWebRTC = true;
		getUserMedia = virtNavigator.mozGetUserMedia.bind(virtNavigator);
		mediaDevices = virtNavigator.mediaDevices;
		RTCPeerConnection = virtGlobal.RTCPeerConnection;
		RTCSessionDescription = virtGlobal.RTCSessionDescription;
		RTCIceCandidate = virtGlobal.RTCIceCandidate;
		MediaStreamTrack = virtGlobal.MediaStreamTrack;
		attachMediaStream = function (element, stream) {
			element.src = URL.createObjectURL(stream);
			return element;
		};
		canRenegotiate = false;
		oldSpecRTCOfferOptions = false;
		// WebRTC plugin required. For example IE or Safari with the Temasys plugin.
	} else if (

// import offline runtime
if (process.env.NODE_ENV === "production") {
  require("offline-plugin/runtime").install();
}

// import global styles
require("globalStyles/reset.css");
require("globalStyles/main.css");

// Add a warning to Firefox users due to a buggy AudioParam implementation
import browser from "bowser";
if (browser.gecko) {
  window.alert(
    "WARNING: Firefox currently has a buggy Web Audio API implementation which causes loud pops and clicks, continue at your own risk"
  );
}

import React from "react";
import { render } from "react-dom";
import { Provider } from "react-redux";
import Loadable from "react-loadable";

import store from "store";
import AppLayout from "layouts/app";

// TODO: Figure out what to do with react-redux's decpricated lifecyles usage
const AsyncMode = React.unstable_AsyncMode;

function filterUnusedVendorRule (selector) {
  if (!(bowser.msedge || bowser.msie) && selector.indexOf('-ms-') > -1) {
    return false
  }

  if (!(bowser.webkit || bowser.msedge || bowser.blink) && selector.indexOf('-webkit-') > -1) {
    return false
  }

  if (!bowser.gecko && selector.indexOf('-moz-') > -1) {
    return false
  }

  return true
}

export default function () {
    if (bowser.tablet) {
        if ((bowser.webkit || bowser.blink) && document.documentElement.webkitRequestFullScreen) {
            document.documentElement.webkitRequestFullScreen();
        }
        if (bowser.gecko && document.documentElement.mozRequestFullScreen) {
            document.documentElement.mozRequestFullScreen();
        }
    }
}

constructor(props: GameWrapperProps, context: any) {
		super(props, context);
		let shouldWarn = false;
		const ignoreWarning = !!+cookie.get("joust_ludicrous", "0");
		if (!ignoreWarning) {
			shouldWarn = !(
				bowser.webkit ||
				(bowser as any).blink ||
				bowser.gecko
			);
		}
		this.state = {
			warnAboutBrowser: shouldWarn,
		};
	}