Hi ledgeri, Firefox allows numerous separate profiles, which are distinct settings folders. However, manually configuring and switching profiles is a bit of a pain so if you can tolerate a little more breakage, you could consider running Firefox Beta or Firefox Developer Edition as your second installation of Firefox. They will automatically default to a separate profile from the regular release of Firefox. If you're interested, see: https://www.mozilla.org/firefox/channel/desktop/

Let's say you want to stick with Firefox release and have separate icons to start in separate profiles. The critical part is this modification to your shortcut Target command line when you want to run a profile other than the default profile:

"C:\Program Files\Mozilla Firefox\firefox.exe" -P "Quantum"

(Your profile names will differ.)

Regarding Sync, I'm not sure. You can select categories of data to sync or not when you configure Sync on the Options page (under Firefox Account). However, that might not be granular enough for your needs.

Oh, more background:

• Profiles - Where Firefox stores your bookmarks, passwords and other user data
• Profile Manager - Create, remove or switch Firefox profiles

jscher2000 said

Hi ledgeri, Firefox allows numerous separate profiles, which are distinct settings folders. However, manually configuring and switching profiles is a bit of a pain so if you can tolerate a little more breakage, you could consider running Firefox Beta or Firefox Developer Edition as your second installation of Firefox. They will automatically default to a separate profile from the regular release of Firefox. If you're interested, see: https://www.mozilla.org/firefox/channel/desktop/ Let's say you want to stick with Firefox release and have separate icons to start in separate profiles. The critical part is this modification to your shortcut Target command line when you want to run a profile other than the default profile: "C:\Program Files\Mozilla Firefox\firefox.exe" -P "Quantum" (Your profile names will differ.) Regarding Sync, I'm not sure. You can select categories of data to sync or not when you configure Sync on the Options page (under Firefox Account). However, that might not be granular enough for your needs.

I would like to reach the state like having 2 seperate browser brand , but with firefox(es), and for for maximal compatibility with the final release versions, not with beta/developement versions, only reaching each other with Sync if needed, not sharing any folders on my system.

Is this possible?

If not, installing beta/Developer next to my main, changines anything (like those using a seperate profiles folder, what includes only their profile folders), or if i have multiple profiles, both instal can access to them, no matter what, because the program works like that, and no way around?

On Windows, Firefox profiles are stored side by side in separate folders. Why not try an experiment to get a better view of it?

New Profile Test

This takes about 3 minutes, plus the time to test some site(s).

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

Click the "Create a New Profile" button, then click Next. Assign a name like June2019, ignore the option to relocate the profile folder, and click the Finish button.

After creating the profile, scroll down to it and click the Launch profile in new browser button.

Firefox should open a new window that looks like a brand new, uncustomized installation. You should not see any of your regular profile data in this profile, although it is still visible in your other Firefox window(s)

Please ignore any tabs enticing you to connect to a Sync account to maintain the isolation.

Firefox will invite you to enable extensions it found in shared locations; these are not specific to any particular profile.

What do you think?

When you are done with the experiment, you can close the extra window without affecting your regular Firefox profile. (June2019 will remain available for future testing.)

On the about:profiles page, you will see the two folders Firefox uses for profile data. Root has the important stuff; Local has cache and other dispensable files.

Does that help?

Note that Firefox itself uses the same program folders regardless of what profile you are running.

jscher2000 said

Note that Firefox itself uses the same program folders regardless of what profile you are running.

This is my problem... i would like to have "an other AppData\Roaming\Mozilla\Firefox\Profiles" folder, like "AppData\Roaming\Mozilla\Firefox\Profiles2" And i want to keep any profile what i use on my primary isntall, to use the first, Profiles folder, and want the second isntall, the other .exe, to have Access to only to " Profiles2" folder. I want a hard seperation on this level, and if needed in other places where it needed to be done to this work properly...

Is this possible to do, OR all in-program references, programming, internal working etc. prevents seperation like this, and without basicly rewriting the entire program, it is totally unavaible?

In more simple way: Can i install two firefox, to be 2 completely seperate programs on the PC , or i always will end up with 2 firefox on my PC wich are using the shared places, like the "Profiles" folder, and other not mentioned places?

The Profiles folder is not the critical factor. One level up from that, in the Firefox folder, is the profiles.ini file. This is what is used to generate the about:profiles page.

You can create secret profiles in random locations and launch them using a command line like this:

"C:\Program Files\Mozilla Firefox\firefox.exe" -profile "D:\Mordor\Dark.Tower"

However, I can't guarantee that Firefox would never add that to your profiles.ini file, and therefore it could eventually show up on the about:profiles page for easy switching. Do you need to avoid that? It sounds like you do.

You could consider creating separate Windows accounts, which have separate C:\Users\username folders. The about:profiles page wouldn't show Firefox profile folders from a different Windows user profile (each user would have a different about:profiles page based on their own profiles.ini file).

With administrative privileges, of course, a user could forcibly cross that barrier, but I assume that is beyond the scope of your request.

Note that current Firefox 67+ releases can lock a profile via installs.ini, so it can only be used by Firefox installed in this specific installation folder.

• https://support.mozilla.org/en-US/kb/dedicated-profiles-firefox-installation

jscher2000 said

Do you need to avoid that? It sounds like you do.

Thanks for the whole message, and conversation!

I do not need to do it, i just thought the 67+ update makes it possible, and i wanted to clarify that, because it sounded to me like it enables the program to work as completely independent from an other installlation, like an other browser/or any other progam would: using individual folders for stuff, not sharing with others... but because this is not the case, i will handle the situation from an other perspective! Not problem to me, just requires an other kind of approach.

Thank you for the informations, and your patience!

cor-el said

Note that current Firefox 67+ releases can lock a profile via installs.ini, so it can only be used by Firefox installed in this specific installation folder.

• https://support.mozilla.org/en-US/kb/dedicated-profiles-firefox-installation

I have checked the installs.ini and profiles.ini . No option to make part of it unavaible for one isntall, and not the other, and the rest reversed, right? That is also an "approach modificator" to me... thanks!

P.S. How can the program handle if one instance running with one profile in use in it, and the other opens the same profile? Can go something wrong? What if both makes modifications in the session, if it was setup to store sessions, then the program not running?

E.g. alpha program opened, running profile one, opening a new tab1; bravo program opened after that, also running profile one, opening new tab2... I had to go, no time to shut down the program, just shutting down my PC, and the OS decides to shut down the programs...

If i open one of the programs with profile one, wich tab what i will see, and why?

Absent other instructions, Firefox 67 will launch the profile currently designated as the default in profiles.ini/installs.ini. Separate instances of Firefox should not run the same profile; there may be an error message, or the request may open in the earlier instance. You can test to see what happens in your configuration as it is not clear what you mean by alpha and bravo.

jscher2000 said

Absent other instructions, Firefox 67 will launch the profile currently designated as the default in profiles.ini/installs.ini. Separate instances of Firefox should not run the same profile; there may be an error message, or the request may open in the earlier instance. You can test to see what happens in your configuration as it is not clear what you mean by alpha and bravo.

I tried it now -...risking my own data, so thanks for that*...- and it opened a blank page like an open new window would, with the settings/plugins of the used profile (with the option enabled to contnue the session).... so because 2 program can open the same profile at the same time -no counter against that-, and with no indicator, which window belongs to wich program, and probably the lates program what closes overwrites the profile what was in use in both -sure i had to test myself.... thanks again*- there is apossibility to session/data loss.

This is not good!

• not personally for you, just for the situation

Is there way to attach something (changed icon on the tray/window), anything to distinguis the windows based on the running instance, if they are opening the same profile? Is there any more detailed source, what i could check what is deeper than the troubleshooting pages above, but not the coding itself? Or this is the deepes level, what i can reach: "asking specific" "Reciving casual" "emphasizing specific" "You can try it yourself" ... not so efficient...

I still don't understand what you are trying to do. What was the first program and what was the second program? What are alpha and bravo?

jscher2000 said

I still don't understand what you are trying to do. What was the first program and what was the second program? What are alpha and bravo?

I installed a firefox into one folder years ago, what is being used since then. (this is the aplha/primary/main/firefox.exe1) I also installed a 2nd firefox into an other folder, days ago. (This is the bravo/secondary/other one/firefox.exe2)

I tried what happens when i open one exe, with one profile, and opening the other exe with the same profile next to it. I have 3 profiles, one old, what i used before knowing what are the profiles, one what i use since i had to try to problemsolve something, and one with a blank profile. All behaves the same:

First try: Opening firefox.exe1,the first time, the profile manager opens, selecting the "boring stuff"profile, it loads the session. Opening firefox.exe2, the first time, profile manager opens, selecting the "boring stuff"profile, it opens a new window into the session. Closing the new window.

Opening firefox.exe2, the Second time time, it opens a new window into the session.

Closing firefox completely.

Second try / n+1 try Opening firefox.exe1,the first time, the profile manager opens, selecting the same profile as above, it loads the session. Opening firefox.exe2, the first time, it opens a new window into the session.

Closing firefox completely.

last try Opening firefox.exe1,the first time, the profile manager opens, selecting the "interesting stuff"profile, it loads the session. and continues like the first try, when starting the firefox.exe2 it opens the manager, but if i select the same profile, it locks itself utnil i close it completely, then after the restart i select an other profile.

What i would like to do Opening firefox.exe1, what opening the profile manager, i can see 'A','B' and 'C' profiles, when i selecting one, and it loads it. Opening firefox.exe2, what always opening the profile manager, i can see '1','2' and '3' profiles (so completely seperate list), and if i select one, it loads it in, no matter what is the state fo the other.

But we closed out the possibility of being able to have 'A','B' and 'C' profiles and '1','2' and '3' in seperate places, or in the same place but with limited visibility... Also would be cool if we could limit firefox.exe2 to be able to launch the same profile what firefox.exe1 currently running, but it can launch it. And by launching it it locks itself onto it until an other "cold start" selects an other profile.

OK, it not creates instant data-loss scenarios, but it makes inconvenient situations...

Yes, it makes sense that two copies of firefox.exe on path1/to/firefox.exe and path2/to/firefox.exe behave identically because they are the identical program and consult the same registry keys and profiles.ini file regardless of installation folder.

jscher2000 said

Yes, it makes sense that two copies of firefox.exe on path1/to/firefox.exe and path2/to/firefox.exe behave identically because they are the identical program and consult the same registry keys and profiles.ini file regardless of installation folder.

Yeah... that what i got wrongly from the patchnotes, and what i wanted to figure/clear out.