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Can I have Firefox 3 and Firefox 4 on the same computer?

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  • Last reply by cor-el

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I am doing a web development and would like to have both Firefox 3 and Firefox 4 on my machine at the same time. Of coarse, I know I can only have one as the default browser at a time. Can I download Firefox 4 into its own folder, install it, and run it so that I can test webpages on both browsers?

I am doing a web development and would like to have both Firefox 3 and Firefox 4 on my machine at the same time. Of coarse, I know I can only have one as the default browser at a time. Can I download Firefox 4 into its own folder, install it, and run it so that I can test webpages on both browsers?

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Do a custom install and install each version in its own program folder to use multiple Firefox versions.

Create a new profile exclusively for each Firefox version and create a desktop shortcut with -P "profile_name" appended to the target to launch each Firefox version with its own profile.

See these mozillaZine KB articles for information:

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Well, I tried to implement this solution but I never received the option to install Firefox 4 in a different location. It immediately wiped out Firefox 3.6.

Is there a way for me to reinstall Firefox 3.6 without de-installing Firefox 4? Can I still download Firefox 3.6? If so, where is located?

Thanks for your help.

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Did you download the full version or did you update?

You should see a radio select box on the second window (click Next once) to do a Custom install after launching the installer.

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I am trying to run Firefox 5 and Firefox 4 on the same computer. Installing 5 to a new directory avoided 4 from being wiped out. But using the Profile Manager option to start Firefox did not change the default profile for either version separately, it changed the profile to the same value for both.

I found out from another similar discussion that if you have the icon for one of the versions run firefox.exe like this -

firefox.exe -P profilename

where profilename is the name of the alternate profile you've created for one version to use, then each version will use a separate profile.

Modified by quadibloc

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