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

  • 2 replies
  • 17 have this problem
  • 6 views
  • Last reply by Carlyle

Carlyle
Carlyle
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I upgraded to Firefox 4 and did not like it. But I'd like to give it another try. Here's the problem: I need a reliable user agent while I'm climbing Firefox 4.0's learning curve, which appears to be steep for me due to many UI changes. More generally, I want a chance to look at Firefox 4.0 *before* I toss out 3.5+ so that I can decide if it is right for me. It might be I need to stick with 3.5+; it might be I need to move to another browser family.

Can I... and how can I... install 4.0 without messing up my 3.6+ installation? Last time I did it, it overwrote my old installation and I had to work to get it back when I decided 4.0 wasn't right for me. I'd rather not have to go through that work again.

I upgraded to Firefox 4 and did not like it. But I'd like to give it another try. Here's the problem: I need a reliable user agent while I'm climbing Firefox 4.0's learning curve, which appears to be steep for me due to many UI changes. More generally, I want a chance to look at Firefox 4.0 *before* I toss out 3.5+ so that I can decide if it is right for me. It might be I need to stick with 3.5+; it might be I need to move to another browser family. Can I... and how can I... install 4.0 without messing up my 3.6+ installation? Last time I did it, it overwrote my old installation and I had to work to get it back when I decided 4.0 wasn't right for me. I'd rather not have to go through that work again.

All Replies (2)

TonyE
TonyE
  • Moderator
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You can install them both but there are a few steps to take.

When you install Firefox 4 use the custom installation option and choose a different location to install Firefox.

In order to use both versions, you need to create a new profile for Firefox 4 (Firefox stores user data in the profile). Using the same profile with different versions can cause problems. Once you create a new profile you can copy certain data such as bookmarks and passwords between them. You can also use Firefox Sync to keep the profile synchronized. Finally, you will need to set up shortcuts to launch the correct profile for each version.

The following links show how to do this:

Carlyle
Carlyle Question owner
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Thanks, this solved my problem. I appreciate the time and trouble you took to find those links.