This is useful when you want to test applications with older or multiple versions of Firefox.
You can install almost all versions of Firefox in one machine and launch them individually.
Below are the steps to do the same.
Firstly download the version/ older versions of Firefox from here you want to install . -> https://ftp.mozilla.org/pub/mozilla.org/firefox/releases/
1) Create new folder on Desktop (or anywhere else).
2) Install Firefox in this folder. When you will install Firefox it will ask for the location to be installed in.
3) Open Command Prompt.
4) Go to directory where Firefox is installed using cd command.
5) Type “Firefox -p”, this will open a Profile manger window for Firefox.
6) Create a new Firefox profile based on the version name you are creating it for ex: p23 or p24
7) Open this folder “C:UsersAdministratorAppDataLocalMozillaProfile” to find the profile you just created.
8) Create shortcut of this newly created profile on Desktop.
9) Right click on the shortcut on open properties.
10) In Target textbox enter the “Destination_of_folder_where_Firefox_is_installedFirefox.exe -p profile_name -no-remote”
e.g. C:UsersAdministatorDesktopf24firefox.exe -p p24 -no-remote
That’s it now click and open this shortcut, what we did is asked this shortcut to use a specfic profile and a specfic version of firefox to be opened.
So now you can open multiple instances of Firefox of different versions simultaneously.
Let me know your feedback.