Ubuntu12.04 install or Upgrade firefox to the latest version (firefox20.0)

Ubuntu12.04 install or Upgrade firefox to the latest version (firefox20.0). Today I used firefox for debugging. I tried F12 and firefox didn't respond. The firebug debugging Panel never came out, so I searched the internet, it is said that the firefox version is low... OK. Update the firefox version. The latest version is firefox20.0, the following update steps: 1, download the latest version: http://firefox.com.cn/download/ 2, delete the old version: [plain] sudo apt-get remove firefox note: I have installed ubuntu in firefox. I didn't install it manually! Use this method to delete the installation in apt-get mode. 3. Install the installation on the ubuntu terminal: [plain] cd/opt # I installed it in the/opt directory, switch to this directory sudo tar-xvf/home/hui/Downloads/Firefox-latest.tar.bz2 # unzip the latest version of firefox to sudo ln-s/opt/firefox/usr/bin/ firefox # create a soft link, enter firefox on the terminal ~ _~ 4. Add the firefox starter: [plain] cd/usr/share/applications sudo vi firefox. the following is an example of desktop configuration: [plain] 1 [Desktop Entry] 2 Version = 20.0 3 Name = firefox 4 Exec =/opt/firefox 5 Terminal = false 6 Icon =/opt/firefox/icons/mozicon128.png 7 Type = Application 8 Categories = after Development is saved, you can search for the latest firefox in dash, with a picture attached: How do you see if it is the latest version? [Plain] firefox -- version