Firefox Support Forum

What is the minimum set of files that I can recreate a FF user profile from?

For example, the official docs say to backup/migrate a user profile by copying the whole directory, but the I'm not interested in the `Crash Reports/` directory, history or any session information.

Based on a post I saw some time ago about Thunderbird user profiles, I would expect that only a few files are actually needed (off the top of my head from the TB example, possibly `cert9.db`, `extensions.json` and `prefs.js`), but I can't find the post again now to double-check and I'm not sure how well it would apply to FF.

So, what files do I need to copy over to a new user profile to retain my:

1. extensions and their preferences
2. Firefox preferences
3. bookmarks

I am running El Capitan and need Firefox 78. I went to a site offering 78 as a download, and version 91.5 came down. Site offering 78esr, same thing. Went to https://ftp.mozilla.org/pub/firefox/releases/ and was unable to figure out how to download 78. Clicking on 78.0 just led to more links that got me nowhere. Is it possible to download version 78 from this or any site? Thank you. heaton5

Hi...please help. Anytime I update anything on Firefox , I end up with a mess. All I did today was make Firefox my default browser. Now, I have lost all my emails and bookmarks. I need back at once please. My talents here are limited and do not understand cyber talk very well. Can someone explain in simple lay person terms how to fix. Thanks Gayle Pugh

The Firefox on my PC abruptly stopped working for pretty much no discernable reason and I don't know what to do. I've tried restarting the PC, uninstalling and reinstalling Firefox and nothing.

I dont get an error message. It just...doesn't start. If I reinstall it, I'm able to get the browser pulled up but then nothing on it works. It won't take me to any websites, it won't open the settings, it won't do anything. Refreshing the browser doesn't work either.

Failing that, I hopped on my phone and attempted to troubleshoot using information on this very site. I discovered that the problem might be stemming from corrupted profile data. I attempted to load the profile manager from Windows using command prompts...but that command doesn't do anything either.

I attempted to find the profile data on my computer and delete it...didn't work. I tried to reinstall Firefox to have it generate new browser data and that didn't work either. I dont know what to do and I dont know I'm supposed to fix this.

Please help, thank you in advance.

I intend to upgrade my desktop PC from Win 8.1 to Win 10 soon due to Microsoft discontinuing support for 8.1 next January and I want to know how to preserve all my current settings in Firefox (including saved Pocket articles). Also, does anyone know for certain whether or not Firefox will be automatically migrated to Win 10 in the upgrade? (If it does, maybe that will answer my first question?)

I was using firefox by downloading it from the website and it was working fine. Then I try searching it in the MS Store to see if updates are possible from there or not and mistakenly downloaded it again. But I cannot see any desktop icon of Firefox other than the one I was previously using. If I go to the MS Store and try opening the app from there then a brand new Firefox opens which I simply cannot delete. I have even went to the Control Pannel to find out if there's another Firefox but there isn't. I am kinda worried as Firefox is my primary browser and I use it for literally every internet related activity. So please help me in uninstalling this second Firefox program which is unwanted here.

Hello, I got a notice when I signed in today to upgrade my Firefox. I followed the instructions for my MAC, and when I went to open up the new application, it said the new version o Firefox does not support my MAC version of 10.10.5 I have been using Firefox forever and love it and unfortunately my MAC is very old (2008) and in order to have a newer version on MAC i need to purchase a new one, which I am unable to do at the moment. Is there any way to reload a older version on Firefox for a MAC 10.10.5? I went searching, but was unable to find one.

Thanks so much Jacqui Cipin

So yesterday I got a new computer and downloaded Firefox to be my default browser. It worked fine the first few hours -- I was able to log into my account, set up my extensions, and use the browser as intended. A few hours in, though, it completely crashed on me. I am unable to go to new websites, refresh a page, open bookmarks, log in to my Firefox account, or even open settings; the home screen also doesn't load when I open a new tab. Literally the only thing I can do is freeze the Bookmarks Toolbar and customize the Toolbar. I tried closing and reopening, refreshing/resetting the browser, restarting my computer, going into Troubleshoot mode, deleting and redownloading the application, but nothing is working. I have no trouble with Firefox on my previous computer or my phone, and Edge is working fine on this computer. I don't know what to do anymore. Any help would be much appreciated.

i just bought my pc with windows10, i installed windows11 ok, but started having problems keeping firefox as my default browser, msn outlook would pop up after i signed into msn calendar app, ended up resetting my computer and mistakenly uninstalled windows11 in the process, i seem to be compounding my problems as i go, im now confused and i need someone to connect to my computer and fix for me, if someone can do this i would be relieved, please let me know if anyone can help..

Upgraded from Windows 10 to 11 and now Fire Fox launches but nothing but a white page. Uninstalled, restarted PC, and tried to reinstall and comes back with: "The code executed cannot proceed because VRUNTIME140_1.dll was not found. Reinstalling the program may fix the problem."

Contacted Microsoft support but they redirected me to Fire Fox support. Any suggestions would be appreciated. I need Fire Fox for a business application that only can be used on Fire Fox.

Thanks.

I have been using Firefox for years but in the last 2 weeks it suddenly started not working properly, being incredibly slow with any search. I uninstalled and re-installed but it still would not work and not it will not even install properly. I have tried about 12 times to install Firefox but it never uploads and works.

I use Windows 11 on Lenovo Yoga, and use the 32 bit version of Firefox. Any ideas what the problem could be?

Chris

I just got a new work laptop. I have exported passwords and bookmarks from FireFox on the old laptop. It seems I am unable to import these now. Any easy way to do this? I have over 624 passwords and no idea the number of bookmarks. Would be painful to have to do this manually. Help please Cheers Kelly

Hi

Did install firefox on a new computer , did copy my profile from the "old" , to the new computer

But no plugins, passwords settings etc where moved to the new computer ?

I have a Win7 machine, and just bought a new Win10 desktop. I followed some instructions from a YouTube solution. From the Help>Troubleshoot>Profile Folder, I copied the profile folder (onto an external drive) and pasted it (from the external drive) onto the new OS(C:) as per instructions.

It did not work, I do not have all my bookmarks and extensions, etc. on the new Firefox browser I have installed on my new machine.

I don't know what to do now. All that was selected and overwritten is still selected on "This PC>OS(C:)" I was tempted to just delete all that shows selected...maybe not a good idea.

I really just wanted to migrate all my bookmarks, but doing the full profile folder seemed like a good idea at the time.... Help Mr. Wizard?!!

I've been using Firefox ESR for some years. Now I would like to know the best way to use and try the "normal" version of Firefox. Can I install it without uninstall ESR? Or must I do a clean install of Firefox after getting rid of ESR? If this is the case, what must I do to keep my profile, bookmarks, etc?