In all the Firefox versions earlier than Firefox 4, there was this orange button present to the extreme right of the location bar. This button is known as the RSS (Really Simple Syndication) button and it helps you to subscribe to a web site’s Posts and comments section.
In the latest version of the Firefox browser, the RSS button is by default not displayed at the right of the address bar instead it is made available through the menu bar of the browser.
Click on the Firefox menu button and then point your mouse over Bookmarks and then place your mouse over Subscribe to this page. Now you can see two menu items namely subscribe to this site’s RSS feed and Subscribe to this site’s Atom feed. Just click on any of the menu items you want and get that site’s RSS feed synced to your browser.
If you find the above procedure lengthy just to get a site’s RSS feed, then you can have the RSS button displayed on the bookmarks bar of your Firefox browser.
Display RSS button next to the Address bar
Right click on an empty area on your tab bar and then click on Customize from the Context menu.
In the Customize Toolbar window thus opened, navigate to the Subscribe button and then click, hold and drag it on to the address bar of your browser.
Now, you should see the Subscribe button present to the next to the address bar of your browser.
That is it, now you can just click on the RSS button displayed in the Bookmarks Toolbar to get a site’s RSS feed.