Enhance Firefox 4 with ten free add-ons

Firefox 4 ( ) is a big improvement over previous versions of the popular Web browser, but you can still teach it plenty of tricks. Here are ten great downloads to help you get more out of Firefox 4 (not all older add-ons work with Firefox 4, but every one in this roundup does). Whether you want to enhance search, better manage the information you find online, keep yourself safe, or perform other Web tasks, we have what you need. And these plug-ins are free.