Hello folks,

working as a web developer, I have  to test my code on older Firefox versions or, just for fun, I want to test browser’s beta version so,  I need to install different versions of it on my computer. If you need something like this, follow these steps and it will be as easy as drinking a glass of water:

1. First of all make a backup copy of your Mozilla profile folder:

   cp /home/your_folder/.mozilla  /home/your_folder/.mozilla_backup

2. After this download the Firefox version you need.
3. Create a new profile using profile manager so that you original profile won’t be affected:

   firefox -profilemanager

4. Unzip the downloaded version in the folder you chose.
5. Create a launcher,  and use the following command:

   /home/your_folder/your_new_firefox_folder/firefox -no-remote -P your_new_profile

Now you can repeat these steps for all the Firefox versions you want to install and use them whenever you need.

Enjoy!