First you can install it using apt-get, You should update your source list.
sudo apt-get update
sudo apt-get dist-upgrade
but if you want to install it manually, here what you should do;
Download then extract as you did already
move the extracted folder to /opt
sudo mv firefox* /opt/firefox38
If you already had a previous Firefox version installed in the /opt directory, remove it with the following command:
sudo mv /opt/firefox /opt/old_firefox
Set up symbolic links
sudo mv /usr/bin/firefox /usr/bin/firefox-old
sudo ln -s /opt/firefox38/firefox /usr/bin/firefox
if everything goes well then you can delete firefox-old in /usr/bin and old_firefox dolder in /opt
bash run-mozilla.shinstead of./run-mozilla.sh? – 0x2b3bfa0 May 19 '15 at 10:32sudo apt-get install firefox– Maythux May 19 '15 at 10:35cat run-mozilla.shto http://paste.ubuntu.com or record it with asciinema? – 0x2b3bfa0 May 19 '15 at 10:35cat run-mozilla.shhttp://paste.ubuntu.com/11223005/ – Shravan40 May 19 '15 at 10:37sudo apt-get install firefoxbut that way i am gettingfirefox version 28whereas i want to use the latest version of it. Even i tried to update it after installing version 28, but i did not work out. – Shravan40 May 19 '15 at 10:39ls? – 0x2b3bfa0 May 19 '15 at 10:40sudo apt-get updateand thensudo apt-get dist-upgrade. V 38 is already in sources now – Maythux May 19 '15 at 10:40lshttp://paste.ubuntu.com/11223074/ – Shravan40 May 19 '15 at 10:42./firefoxor./firefox-bin? – 0x2b3bfa0 May 19 '15 at 10:44