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Should I do an upgrade or a completly new install with a new profile

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  • Last reply by cor-el

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I last used Firefox regularly over a year ago when the upgrade to version 4 caused excessive memory use and FF to regularly freeze.

Given the problems I experienced at the time & the multiple versions since then:

1. would it be preferable to do a separate installation of the new version with a new profile

2. how do I do this and keep my old version so that I can use it as a reference for bookmarks, plugins, etc.

I last used Firefox regularly over a year ago when the upgrade to version 4 caused excessive memory use and FF to regularly freeze. Given the problems I experienced at the time & the multiple versions since then: 1. would it be preferable to do a separate installation of the new version with a new profile 2. how do I do this and keep my old version so that I can use it as a reference for bookmarks, plugins, etc.

Modified by IslanderCirce

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You can install multiple Firefox versions via a custom install in different installation folders and use a separate profile folder for each version.


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

Make sure not to start Firefox after the installation has finished.
Create a new profile exclusively for each Firefox version.
Create a desktop shortcut with -P "profile" appended to the target to launch each Firefox version with its own profile.

See these mozillaZine KB articles for information:


You can find the latest Firefox release in all languages and for all Operating Systems here: