[ -e /usr/bin/firefox ] && rm /usr/bin/firefox \                                                                                                                                                      
&& wget -P /tmp/ https://ftp.mozilla.org/pub/mozilla.org/firefox/releases/33.1.1/linux-x86_64/en-US/firefox-33.1.1.tar.bz2 \
&& tar -xvjf /tmp/firefox-33.1.1.tar.bz2 -C /opt/