Install Firefox on Linux

I have faced this issue that no article or no forum shows correct way to install firefox on debian based distros, or maybe I haven't found such article, but anyways I figured out myself.

Step 1
Download your desired firefox browser.

Step 2
Extract firefox tar file and it should give you the internal firefox folder in your downloads folder.

Step 3
Now to move that extracted firefox folder to /opt directory.

sudo mv ~/Downloads/firefox /opt

Step 4
Now to create firefox's .desktop file in user's applications directory

cd ~/.local/share/applications

You can name your firefox desktop file anything like I have installed firefox developer addition, so my file name is firefox-dev.desktop. But you can name it anything which is relevant.

touch firefox-dev.desktop
nano firefox-dev.desktop

Inside this file my configuration is something like this:

[Desktop Entry]
Encoding=UTF-8
Version=1.0
Type=Application
Exec=/opt/firefox/firefox
Name=Firefox Developer Edition
Icon=/opt/firefox/browser/chrome/icons/default/default128.png
Comment=Custom definition for Firefox Developer Edition
Terminal=fasle

Note:

1. You can see that location to execute firefox is in out /opt/firefox pointing to firefox executable file.
2. Icon for out firefox will be found in given location, you can choose any set of icons, whichever suits your need.