A text like "Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040207 Firefox/0.8" seems very common... But how about changing the whole identity of your browser?
It's possible!
RPMs (Redhat Packages Manager) is a powerful Package Manager, which can be used to build, install, query, verify, update, and erase individual software packages...
But do you master it?
When I used to use RedHat 9, there was no graphical font installer under KDE, and even with Fedora, fonts are just installed for KDE, not GTK applications (Mozilla, Gimp, etc.)...