It was just like a regular day and I was going through few sites, suddenly I felt to checkout if there is any new version of Firefox has came up (I check bi-weekly). And yeah, there was new version available. As usual, I tried to upgrade using the Help > About firefox menu and it showed that there is new version is availble. While usually it updates the firefox without doing much and just by opening About box, but this time it failed. So to get the latest version, I tried to download it manually. Hmm… and then I was bit shocked by the installer.