Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

How to install multiple Firefox versions

  • 6 replies
  • 2 have this problem
  • 20 views
  • Last reply by McPrell

more options

For many years I'm using Firefox on several versions of Mac OS X. Due to compatibility reasons I have to keep the latest 3.6.28 and I would like to use the latest version.

Until version 35.0.1 there was not a problem at all to have multiple versions installed. The problem started with 36.x and also remains with the very latest 38.0.

Problem: all booksmarks disappear when switching between versions. Browser history also disappears. How to reproduce the problem: I'm launching the old version 3.x, all booksmarks are there. Then I'm shutting down 3.x. Then I'm launching the latest version 36.x or 37.x or 38.x and all booksmarks are still there. Then I'm shutting down this version. Back to 3.x all bookmarks are gone. In any FF version.

I need to recover the Firefox folder in the Application Folder to get back to the 35.0.1.

Any help would be really appreciated.

Best Wishes from Germany,

Boris

For many years I'm using Firefox on several versions of Mac OS X. Due to compatibility reasons I have to keep the latest 3.6.28 and I would like to use the latest version. Until version 35.0.1 there was not a problem at all to have multiple versions installed. The problem started with 36.x and also remains with the very latest 38.0. Problem: all booksmarks disappear when switching between versions. Browser history also disappears. How to reproduce the problem: I'm launching the old version 3.x, all booksmarks are there. Then I'm shutting down 3.x. Then I'm launching the latest version 36.x or 37.x or 38.x and all booksmarks are still there. Then I'm shutting down this version. Back to 3.x all bookmarks are gone. In any FF version. I need to recover the Firefox folder in the Application Folder to get back to the 35.0.1. Any help would be really appreciated. Best Wishes from Germany, Boris

All Replies (6)

more options

Newer version of firefox use a different file format for storing bookmarks and other data, which means it is no longer possible to transfer information between the two. If you want, you can use two separate folders to store your firefox data for each version. Firefox Portable will let you do this, but note that it is not made by Mozilla.

more options

Portable Apps is Windows OS only programs - they don't have a Mac version of Firefox Portable. I have seen a few different versions (in past years) of 'Portable' that were made by a Mac Users Group, but nothing as "new" as 3.6.28.

What the thread owner needs is a separate Profile for each version of Firefox, and a specific desktop shortcut so that the correct Profile is launched. I don't know how that is done on a Mac. Here's the KB article about Profiles. Profiles - Where Firefox stores your bookmarks, passwords and other user data

more options
more options

Yes it sounds like you are sharing the same Profile between the major difference of versions.

The basics has always been to have Firefox versions in separate folders and have each version with its own Profile.

more options

Chosen Solution

more options

Thanks a lot, I created a second profile instead of sharing the profile for both version and it works perfectly!