Windows 7: How to use both Firefox 3 & 4, and easily switch between them !

hi !

The “EASY” way to run both Firefox 3 & 4:

1. duplicate the existing profile
2. name them F3 & F4
3. duplicate profiles.ini
4. name them profiles.F3 & profiles.F4
5. create a bat-file, Firefox 3.bat:

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COPY C:\Users\HACKERMAN\AppData\Roaming\Mozilla\Firefox\profiles.F3 C:\Users\HACKERMAN\AppData\Roaming\Mozilla\Firefox\profiles.ini

START "" "E:\SYSTEM\FIREFOX 3.lnk"

EXIT
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6. create a shortcut to Firefox 3, (firefox.exe in the firefox-3 folder), name it FIREFOX 3

7. create a bat-file, Firefox 4.bat:

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COPY C:\Users\HACKERMAN\AppData\Roaming\Mozilla\Firefox\profiles.F4 C:\Users\HACKERMAN\AppData\Roaming\Mozilla\Firefox\profiles.ini

START "" "E:\SYSTEM\FIREFOX 4.lnk"

EXIT
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8. create a shortcut to Firefox 4, (firefox.exe in the firefox-4 beta folder), name it FIREFOX 4



9. create shortcuts to Firefox 3.bat & Firefox 4.bat, put them on your taskbar / desktop.


both bat-files & both shortcuts (Firefox 3.lnk & Firefox 4.lnk) should be in the same folder: "E:\SYSTEM"
now you can use both versions without having any trouble with your add-ons etc. since each version uses its own profile.

NOTE: the bat-files above are of course only examples !

of course you can change the paths, "E:\SYSTEM\" is where i have MY bat-files & shortcuts.
you should also change the paths in the bat-files to fx. C:\Users\%username%\.....", or your own username instead of "HACKERMAN".

but there is one good reason why i use direct and not relative addressing in the path,
if i use my ADMIN-account instead of my USER-account then i can still use the same profiles.
otherwise i would have to create double profiles also on my ADMIN-account, and i would also have to update / synchronize the profiles on both accounts.

why use shortcuts to firefox.exe in both bat-files ?

otherwise you would have to use direct addressing, and have to switch folder (cd "C:\Program files\....", before starting firefox.exe,
but since shortcuts "know" where the exe-file are, it´s easier to use a shortcut.
also if you change folder fx. when installing a new version if Firefox, then you only need to change the shortcut, not the bat-file.

This method is easier: Run Firefox 3.6 and Firefox 4 Beta Simultaneously - TechSpot