Maintain Session Storage Across Tabs. NOT created by me all credit to: http://blog.guya.net/2015/06/12/sharing-sessionstorage-between-tabs-for-secure-multi-tab-authentication/

sessionStorageTabs.js

(function() {
        
        //source: http://blog.guya.net/2015/06/12/sharing-sessionstorage-between-tabs-for-secure-multi-tab-authentication/ 
        
	if (!sessionStorage.length) {
		// Ask other tabs for session storage
		localStorage.setItem('getSessionStorage', Date.now());
	};

	window.addEventListener('storage', function(event) {

		//console.log('storage event', event);

		if (event.key == 'getSessionStorage') {
			// Some tab asked for the sessionStorage -> send it

			localStorage.setItem('sessionStorage', JSON.stringify(sessionStorage));
			localStorage.removeItem('sessionStorage');

		} else if (event.key == 'sessionStorage' && !sessionStorage.length) {
			// sessionStorage is empty -> fill it

			var data = JSON.parse(event.newValue),
						value;

			for (key in data) {
				sessionStorage.setItem(key, data[key]);
			}

			showSessionStorage();
		}
	});

	window.onbeforeunload = function() {
		//sessionStorage.clear();
	};


})();