Download from the link, I provided.
Then unzip the file, open Firefox and goto Tools -> Extensions, now simply drag-n-drop the extracted file from the HDD into Extensions windows of firefox, it'll install it, now close & reopen the browser.
Firefox :: 100 Million Downloads - Still Going Strong
I was surprised to see this article in Today's "The Hindu". If such a local paper devotes a portion of their last page for an article on Firefox, then it means that Firefox's grip on the general public has tightened. Go Firefox!!
A weather balloon satellite will be launched to celebrate 100 million downloads of Mozilla Firefox. The Oregon NASA Space Grant Consortium balloon satellite, dubbed Firefox One, is expected to reach a height of 100,000 feet (about 30 kilometres or 19 miles) when it's launched from the Memorial Union Quad at the Oregon State University campus in Corvallis, Oregon (north-western United States) at noon on Saturday. It will carry a payload of a large Firefox banner, a Firefox CD-ROM and a camera to "take photos of Firefox at the edge of space".
The stunt, which marks the 100 million Firefox download milestone reached earlier this week, is being coordinated by the Oregon State University Linux Users Group, the Oregon NASA Space Grant Consortium and the Oregon State University Open Source Lab. The Open Source Lab is already a major contributor to the Mozilla project and provides hosting facilities for some of the Mozilla servers. The Open Source Lab also hosts MozillaZine.
Spectators are advised to arrive at about 11:45am. For those who cannot make it in person, the event will be viewable on the Memorial Union Quad webcam.
Previously, the Oregon State University Linux Users Group chalked a giant Firefox logo on the Memorial Union Quad to celebrate Mozilla Firefox's fifty millionth download earlier this year. More details of this and other fifty million download celebrations can be found on the Spread Firefox Blazing a Trail to 50,000,000 page.