So I downloaded the full firefox installer here: https://www.mozilla.org/en-US/firefox/all/, which seems to be the most common solution for people having trouble installing the program through the "stub" installer, but that still hasn't done it for me. When I run the installer I get a little window that says "extracting" with a loading bar below it. It completes the extracting process, but then nothing happens. The window disappears and nothing else pops up to continue with the installation... please help!