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i installed firefox 4 and downloaded firefox 3.6 because molybdenum is not available for ff4!

firefox 3.6 is located /usr/local/share/firefox-36/firefox (only root can run ff3.6).

if the user "peter" goes to /usr/local/share/firefox-36/ and run firefox, firefox 4 startsup instead of firefox 3.6!

Is there any workaround to start ff36 as "peter"?

  • EDIT:

If i use --debug this get prited to console

peter@muhahaha:/usr/local/share/firefox-36$ ./firefox --debug
./ -g ./firefox-bin
/usr/bin/gdb --args ./firefox-bin
GNU gdb (Ubuntu/Linaro 7.2-1ubuntu11) 7.2
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
Reading symbols from /usr/local/share/firefox-36/firefox-bin...(no debugging symbols     found)...done.
  • Update: A few days later the versions switched: i can start ff4 only as root, users always start ff36 now!
share|improve this question
Have you tried to run /usr/local/share/firefox-36/firefox?. Using all the path. – Javier Rivera Dec 2 '11 at 12:41
Are you sure you're running firefox, and not – RobinJ Dec 2 '11 at 12:42
@JavierRivera, i have tried that - but it starts ff40 – Peter Rader Dec 2 '11 at 14:03
@RobinJ, there is no /usr/local/share/firefox-36/ For FF4 the file /usr/lib/firefox-4.0/ exists, but im currently located to /usr/local/share/firefox-36/ – Peter Rader Dec 2 '11 at 14:05
@PeterRader: Is there any reason why you want to keep FF4? – Count Zero Dec 5 '11 at 18:56
up vote 0 down vote accepted

Firefox usually check for compatibility as standard procedure when installing new plugins, you can disable this by using an add-on like or using the appropriate flag under about:config .

Running 2 different versions of Firefox can lead to unwanted behaviours or worst to the loss of your personal data.

share|improve this answer
interresting, but does not solve my problem – Peter Rader Dec 5 '11 at 14:31
what do you mean? the installation of the plugin you want or the execution of two different versions of Firefox? This should solve your first problem. – Micro Dec 5 '11 at 14:33
hm, im not sure, your answer make my workaround needless but does not help to solve the problem titled in heading. If after a few days no better answer has been posted, ill give you the 100 bounty – Peter Rader Dec 5 '11 at 14:47
Running two different versions of Firefox at the same time or under the same userspace it's really unsafe because no matter what Firefox looks every single time for its own home folder ~/.mozilla and differents versions of Firefox provide different organization and data for this folder, it's true that the basic skeleton contemplates the presence of common files like key3.db or signons.sqlite but it can occur that with a new version some files can be deleted or merged togheter and you can lost your data doing this back and forth. – Micro Dec 5 '11 at 14:56
you are right, and that's what sachin jain wrote, he is right also. But I agree with the comment of WarriorIng64 also. – Peter Rader Dec 5 '11 at 15:03

To have two versions of firefox to run - you'll need to create separate profiles. If you don't, you will get clashing addons and possibly a corrupted shared profile.

I'm not sure how you installed firefox 4 - it no longer appears in the mozilla releases folder

On my computer I have the standard firefox 8.0 installed with Natty.

I downloaded firefox 3.6 tar file from the Mozilla releases folder and untar'ed it:

cd Downloads
tar xjf firefox-3.6.24.tar.bz2
cd firefox

Then create a profile for firefox 3.6

./firefox -ProfileManager

call the profile firefox36 - note the ./ is significant to run the local copy of firefox.

When you want to run firefox 3.6

cd ~/Downloads/firefox
./firefox -P firefox36

Similarly create a profile for firefox 8

firefox -ProfileManager

call the profile firefox8

When you want to run firefox 8 run

firefox -P firefox8

the only caveat - dont run both browsers at the same time.

You've possibly permissions/corruptions due to running Firefox as root - if you run Firefox as root, then various files can be updated with root permissions. When you use firefox as a standard user, the same files will fail to update.

These steps below should give you a clean start with no profiles and incorrect file permissions.

  1. I would purge your current firefox (sudo apt-get purge firefox) -and then reinstall.
  2. I would remove your /user/local/share version of firefox - and install firefox 3.6 locally as per my answer.
  3. I would rename/remove the .mozilla folder in your home folder.
share|improve this answer
Hm... now i have 4 profiles: two for 'peter' and two for 'root'. I still can't start any profiles of ff4 as 'peter', and i still can't start any profiles of ff36 as 'root'. To run firefox -P Firefox4 does not work for 'peter'. – Peter Rader Dec 6 '11 at 9:55
@PeterRader - sounds like you've got possibly permissions/corruptions due to running Firefox as root. I would purge your current firefox (sudo apt-get purge firefox) -and then reinstall. I would remove your /user/local/share version of firefox - and install firefox 3.6 locally as per my answer. I would rename/remove the ".mozilla" folder in your home folder. You should then be starting from a clean start with no profiles. – fossfreedom Dec 6 '11 at 10:04

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