title="&helloworld.clock;" buttons="accept"
   onload="initClock();">
 <script type="application/javascript" src="chrome://helloworld/content/clock.js" />
 <hbox align="center">
   <label value="&helloworld.currentTime;:" />
   <textbox id="currentTime" />
 </hbox>

 showCurrentTime();
 window.setInterval(showCurrentTime, 1000);

 var textbox = document.getElementById("currentTime");
 textbox.value = new Date().toLocaleTimeString();
 textbox.select();
 

I am trying to get active Tab Title as well as URL from Mozilla Firefox. I have started to build up a Firefox add on and installed it using registry entry. My own developed Firefox add on is installed perfectly and it is showing the current machine time. This Firefox add on contains file like chrome.manifest, install.rdf, sample.xul, overlay.xul, clock.xul, clock.js etc. Below is my code. chrome.manifest ---- content helloworld jar:chrome/helloworld.jar!/content/ overlay chrome://browser/content/browser.xul chrome://helloworld/content/overlay.xul locale helloworld en-US jar:chrome/helloworld.jar!/locale/en-US/ locale helloworld fr-FR jar:chrome/helloworld.jar!/locale/fr-FR/ skin helloworld classic/1.0 jar:chrome/helloworld.jar!/skin/classic/ style chrome://browser/content/browser.xul chrome://helloworld/skin/overlay.css style chrome://global/content/customizeToolbar.xul chrome://helloworld/skin/overlay.css clock.xul---- <?xml version="1.0"?> <?xml-stylesheet href="chrome://global/skin/"?> <!DOCTYPE dialog SYSTEM "chrome://helloworld/locale/clock.dtd"> <dialog id="clockDialog" xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" title="&helloworld.clock;" buttons="accept" onload="initClock();"> <script type="application/javascript" src="chrome://helloworld/content/clock.js" /> <hbox align="center"> <label value="&helloworld.currentTime;:" /> <textbox id="currentTime" /> </hbox> </dialog> clock.js----- function initClock() { showCurrentTime(); window.setInterval(showCurrentTime, 1000); } function showCurrentTime() { var textbox = document.getElementById("currentTime"); textbox.value = new Date().toLocaleTimeString(); textbox.select(); } I want to convert this code to fetch current tab title and URL from Firefox browser. At first, I am concentrating on the browser extension part and not the native for now and I just want to have a listener inside the js files such that whenever I switch to a different firefox tab or firefox window, an alert should show up from the browser itself (not from native at this moment) displaying the active tab's title and URL. I want to get the solutions it code . It would be great help if any one can help me to get the exact solutions.