March 22, 2011, 9:26 PM — A lot has changed in the browser universe since Firefox 3.0 launched in June 2008. Google Chrome burst onto the scene, and has undergone frequent updates since then. Microsoft released IE 8 and IE 9. Safari advanced from version 3 then to version 5 now.
While Mozilla made some improvements in Firefox 3.5 and 3.6 that improved performance and bolstered the feature set, Firefox started to feel like it was falling behind the curve. Firefox 4 makes Firefox competitive again, with its updated interface and improved performance.
Firefox Gets a Makeover
The first thing you'll notice is that Firefox 4 has a new look. Like many other modern browsers, Firefox 4 is designed to be as streamlined and as simple as possible. The Mozilla designers did a good job at simplifying the browser while maintaining the flexibility that Firefox is known for.
By default, Firefox 4 shows the address bar, a search field, the typical back/forward/reload/home buttons, the tab bar, and an orange "Firefox" button in the upper-left corner. There is no menu bar by default: Clicking the orange Firefox button brings up a single, well laid-out menu that contains most--if not all--of the menu items you're accustomed to using in older Firefox versions. I was a little thrown off by this button, though; most new browsers have their tools menus on the far-right edge of the toolbar, whereas the Firefox button is on the upper-left, but I was able to adjust fairly quickly.
If you're a Firefox power user--or just prefer the old way--you can bring back the classic menu bar by clicking the Firefox button, mousing over "Options," then selecting "Menu Bar" from the drop-down.
Pinning Web Apps
Another Chrome-inspired feature in Firefox 4 is the ability to "pin" Web apps to the tab bar. Open up any Web app (or any Web page, really) in a new tab, right click the tab, then select "Pin as App Tab." This will add a tab showing only that page's icon to the far left edge of the tab bar.
When you close then re-open Firefox, the pinned tabs will remain there. Whenever something in the Web app you pin updates--say, you get a new message in your Gmail inbox--the pinned tab will turn blue to notify you (again, very similar to Google Chrome).