The recently revamped version of Facebook Chat was pissing everyone off. Mostly due to the fact that it took a whole lot of space of the page and didn’t bother to filter offline and online friends. We have got a way to fix this issue easily with just a few clicks.
Let me say something important in the start, this method won’t work on Internet Explorer. At least for now, there isn’t any way to revert back to the old chat in Internet Explorer. This method can only be used with Mozilla Firefox and Google Chrome. They are much better browsers then Internet Explorer so you won’t miss anything.
Ok, now for the guide. Follow the steps below for your preferred browser.
Mozilla Firefox 
1. Install this add-on from here. This add-on allows personal script to be able to run on Firefox. This is quite old and handy add-on and one of our favorite.
2. Install this script from here. You will have to use this script in greasemonkey add-on. This will revert the old chat back finally!!
3. After installing the script, do a soft reset in Forefox by pressing CTRL+R. Voila!! Enjoy the old chat.
Google Chrome
1. You don’t need any add-on here. Just install this script from here.
2. Restart your browser and enjoy the classic Facebook chat.