What are profiles in Mozilla Firefox? This is a set of settings, user information. Firefox can be run with a specific profile, and then Firefox will have its own settings, plugins, external display, and more. It's almost like having Firefox installed and configured separately.
This way you can create profiles for different users or for one user, but for different tasks.
For example, I needed profiles:
- for everyday work on the Internet - social networks, authorization on the necessary sites, necessary bookmarks, your own history of visiting;
- for work - this is authorization, remembering authorization on specific sites. Authorization of other accounts in social networks and so on.
- for mom 🙂 Link to classmates in bookmarks in the most prominent place and authorization with memorization on the same site 🙂
Application may vary.
So what exactly is stored in profiles:
- Bookmarks and browsing history
- Passwords
- Special site settings
- search engines
- Personal dictionary
- Autocomplete fields
- Cookies
- Security certificate settings
- File type management
- User styles
Also, for each profile, you can set your own design and add-ons installed in Firefox in the current profile will also be available only in this profile.
How to manage Firefox profiles?
To do this, you need to start Firefox with the parameter. You can do this, Start -> Run and then enter (before that, you will need to close all open Firefox windows, otherwise executing the following command will simply launch the browser, not the profile manager)
firefox.exe -ProfileManager
I just want to note that the checkboxes in the window affect the current launch of the browser. Work offline - means that the browser will work offline (with)CEP.
If you select any of the profiles and check the "Do not ask at startup" checkbox, then the next time you start the browser without specifying a profile, it will start with the selected profile. If you uncheck the box, then every time you start the browser, you will be prompted to select a personal profile. If you checked the “Do not ask at startup” checkbox, but after that you needed to change the profile loaded by default, then you will need to start the profile manager again, as described above, and set the necessary settings.
Where is the profile stored? In my Windows XP files are stored here. One profile - one folder, for example zwv9xv8q.lampdevru.
C:\Documents and Settings\username\Application Data\Mozilla\Firefox\Profiles
C:\Documents and Settings\username\Application Data\Mozilla\\Profiles |
You can also open the profile folder by doing the following: select the menu item Help -> Troubleshooting Information or in a new tab in the address bar we write about: support, the page loads, we see the following
How to start Firefox with the right profile?
To do this, the executable file must be launched with the parameter -p profilename. For example, you can create a shortcut and write the following in the "Object" property
Firefox has its own profile system that works like a Chrome user account switcher. Each profile has its own bookmarks, settings, extensions, browser history, cookies and other data. For example, you can create a profile for work and a separate profile for personal use.
Mozilla hides Firefox's profile manager instead of making it a prominent part of the interface like Chrome does, for example. But, if you want to use different browser profiles with your own settings and data, Firefox allows it.
Containers with multiple accounts in Firefox
Mozilla has another, more streamlined solution if you just want parts of your browser to be separated from each other. The extension is called "Firefox Multi-Account Containers" and it's made by Mozilla themselves. This extension allows you to select a "Container" for each open tab. For example, you can run tabs in the Work container when you are working and the Personal container when you are not working. So, if you have a separate set of work accounts and personal accounts, then you can simply switch between containers without logging in and out of each website.
While this does not completely replace the need for profiles (bookmarks, browser history and extensions are shared between containers), it does allow you to have separate login state and cookies for each container.
How to create profiles and switch between them
Mozilla Firefox now allows you to manage profiles while you work, without having to use the Profile Manager available in older versions. To access this feature, type " about:profiles' in the Firefox address bar, and then press Enter. You can bookmark this page for easier access in the future if you wish.
If you haven't viewed Firefox profiles before, you'll probably be using the "default" profile.
To create a new profile, click the "Create a new profile" button.
In the Profile Wizard window that appears, provide a descriptive name for the new profile so you can remember what it is for. For example, you can name it "Work profile" if it is intended for work.
To start Firefox with a new profile, first click the "Set as default profile" button in the profile. Once it becomes your default profile, close all open Firefox browser windows and restart Firefox. It will start with the default profile selected.
To switch back to a different profile, go to profiles again: click "Set as default profile" for the profile you want to use, and then restart Firefox.
If you no longer need a profile, you can click the "Remove" button to remove it from your system. Keep in mind that this will delete all data saved on the profile, including its bookmarks, saved passwords, and extensions.
How to use multiple profiles at once
You may have noticed that the "About Profiles" page has a "Launch another browser with this profile" button. However, this button does nothing when using the default Firefox configuration for handling profiles. By default, Firefox only runs one profile at a time. You need to close and restart your browser to switch between profiles. But by slightly changing the shortcut you use to launch it, Firefox can launch multiple profiles at the same time.
To enable multiple Firefox profiles at once, you must start Firefox with the option -no-remote. To do this, you need to edit the shortcut in the Taskbar, on the Desktop or in the Start menu, which is usually used to launch Firefox.
For example, if you use the shortcut on the taskbar to launch Firefox, right-click on the Firefox icon on the taskbar, right-click on "Mozilla Firefox" in the pop-up menu, and select "Properties".
In the Properties window, on the Shortcut tab, place the cursor at the very end of the text in the Target field, and then add -no-remote to the end of the text. The Object field should look something like this:
"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -no-remote
Close all open Firefox browser windows, and then restart Firefox using the shortcut you just changed. When you do this, you can return to the page about:profiles and click the "Launch another browser with this profile" button. Firefox will open a new browser window with the selected profile.
Using the old profile manager
You can also do everything we talked about with the old Firefox profile manager if you like. It also allows you to create custom shortcuts that open the Firefox Profile Manager and launch Firefox with specific profiles, if you like.
First, you need to completely close Firefox. Then you need to launch Firefox with the key -p.
- On Windows: press Windows + R, type firefox.exe -p in the Run window that appears, and then press Enter.
- On Mac: open a terminal window - press Command + Space, type Terminal and press Enter to do this from Spotlight. At the command line, type /Applications/Firefox.app/Contents/MacOS/firefox-bin-profilemanage r and press the Enter key.
- On Linux: open terminal and run firefox -profilemanager command.
You will see the "Select User Profile" dialog box. By default, one user profile named "default" will be created. You can use this window to create additional profiles, rename existing ones, and delete them.
If you want to always see the profile selection when you start Firefox, which will allow you to select a profile every time you click on the Firefox shortcut without using a special command, you can disable "Run the selected profile without prompting". This will make Firefox ask which profile you want to use until you enable this option.
At least one profile is required to use Firefox. Each profile has its own settings, extensions, bookmarks, history, cookies and everything else. Keep this in mind. If you delete the "default" profile, you will lose all Firefox browsing data (unless you are using Firefox Sync).
When you create a new profile, you can give it any name you want. The wizard will show you where the profile will be stored. By default, they are placed in your user account's Firefox profiles folder, prefixed with eight random letters and numbers.
Select a profile and click Launch Firefox to launch Firefox with the selected profile. When you first start Firefox with a new profile, you will see a welcome message.
Close Firefox and restart it to switch between profiles. If you have disabled the "Run the selected profile without prompting" option, then Firefox will ask which profile you want to use before launching. You can also leave this box checked and launch Firefox using the toggle -p or -profilemanager to access the hidden profile manager whenever you want.
For ease of use, you can create a shortcut that will also open Firefox using the profile manager. For example, on Windows, you can create a copy of the Mozilla Firefox desktop shortcut, rename it "Mozilla Firefox - Profile Manager" and then add a space and -p to the end of the text in "Object". This shortcut will now open Firefox using the Profile Manager, assuming Firefox is completely closed when the shortcut is launched.
By default, Firefox doesn't work the way Chrome does. He wants you to use one profile at a time. However, if you wish, you can use multiple profiles at once.
To do this, you just need to start Firefox with the key -no-remote. You can do this in the Run dialog or Terminal, or you can simply change an existing Firefox shortcut. For example, if you have created a profile manager shortcut, you can simply add -no-remote to make it work -p -no-remote at the end of the Object field.
Start Firefox with this switch, in other words, double-click on the shortcut you just created and it won't check if Firefox is already running. Instead, it will ask which profile you want to use, and create a new Firefox process with that profile.
You can use this process to open Firefox with any number of different profiles, although each profile can only be used by one copy of Firefox at a time. If you try to open the same profile a second time when it is already running, you will see an error that the profile is already in use.
Note. If you see an error using a profile while Firefox is closed, you may need to visit the task manager and kill the firefox.exe process from there, force close it if it is running in the background.
Everything should work as you would expect. However, while Chrome does make it easy to see the profile you're using in its interface, Firefox doesn't make this information very visible. To do this, you can set a different theme for each profile to visually differentiate them.
If you ever need to find out which profile you are using, you can find this information on the " about:profiles».
You do not need to use the Profile Manager to troubleshoot problems with your Firefox profile. Instead, you can use the "Reset Firefox" feature to get the Firefox browser back to its original settings without losing important things.
Firefox saves your personal information such as bookmarks, passwords, and user preferences in a set of files called your , which is stored in a separate location from the Firefox program files. You can have multiple Firefox profiles, each containing a separate set of user information. The Profile Manager allows you to create, remove, rename, and switch profiles.
- If you have (or plan to have) multiple installations of Firefox on one computer, see Dedicated profiles per Firefox installation .
- If you are troubleshooting a problem with Firefox: The Refresh Firefox feature can fix many issues by restoring Firefox to its default state while saving your essential information. Consider using it before going through a lengthy troubleshooting process.
Table of Contents
Starting the Profile Manager
Manage profiles when Firefox is open
type about:profiles into the address bar and press the Enterreturn key. This will open the About Profiles page.
The following options are available:
To manage profiles, find the profile you want to change and choose from these buttons underneath that profile:
- Rename Click this to change the name of a profile in the Profile Manager. Note: The folder containing the files for the profile is not renamed.
- Set as default profile This option allows you to switch profiles. Click this to make Firefox use this profile by default at startup.
- Launch profile in new browser When you click this, another Firefox window will open using that profile.
Start the Profile Manager when Firefox is closed
Note: Another way to start the Profile Manager is from the Search box in the Windows Start menu. Close Firefox (if open), press , type firefox.exe -P and press enter.
If the above instructions do not work or if you have multiple installations of Firefox, use the following instructions instead.
Multiple Firefox installations
You can have multiple Firefox programs installed in different locations. To start the Profile Manager for a specific Firefox installation, replace firefox.exe in the above instructions with the full path to the Firefox program, enclose that line in quotes, then add a space followed by -P.
Examples:
Firefox (32-bit) on 64-bit Windows
"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -P
Removing a profile
After starting the Profile Manager as explained above, you can remove an existing profile as follows:
Renaming a profile
After starting the Profile Manager as explained above, you can rename a profile as follows:
- In the Profile Manager, select the profile to rename, and then click Rename Profile... .
- Enter the new name for the profile. Type in the new profile name, and click on OK .
- note: The folder containing the files for the profile is not renamed.
Options
Work Offline
Choosing this option loads the selected profile and starts Firefox without connecting to the Internet. You can view previously viewed web pages and experiment with your profile.
Use the selected profile without asking at startup
When you have multiple profiles, this option tells Firefox what to do at startup:
- If you check this option, Firefox will automatically load the selected profile at startup. To access other profiles, you must start the Profile Manager first.
- If you uncheck this option, Firefox will show you the Profile Manager each time you start Firefox, so that you can select a profile to use.
Use Sync with a new profile
When you first open Firefox in a new profile, a Welcome to Firefox page will open, with a space to enter your email address.
What is a profile?
Firefox stores all the information that a user generates while using the browser in a special folder called a profile. Data such as bookmarks, cookies, browsing history, browser settings and installed add-ons, remembered passwords are saved. When you first start Firefox, a profile is created with default settings.
Profile Folder Location
Depending on the operating system, the default profile folder is located in the following paths.
If you created this folder yourself through the profile manager and specified a path other than the suggested one, the profile folder may be located in a different location.
Windows 95, 98 and ME
C:\Windows\Application Data\Mozilla\Firefox\Profiles\ Select "Start → Run"; Enter %APPDATA%; Click OK. A Windows Explorer window will appear; In the Windows Explorer window, select "Mozilla → Firefox → Profiles". Each subfolder in this folder is a profile on your computer. C:\Documents and Settings\ The "Application Data" folder is a hidden folder. To show hidden folders, open Windows Explorer and select: "Tools → Folder Options → View tab → Show hidden files and folders". Press the start button to open the menu; Enter %APPDATA% in the "Start Search" field; Click on the “Roaming” item that appears in the menu; In the Windows Explorer window that opens, select "Mozilla → Firefox → Profiles". Each subfolder in this folder is a profile on your computer. You can also directly navigate to this folder using the following path: C:\Users\ The "AppData" folder is a hidden folder. To show hidden folders, open Windows Explorer and select: Organize → Folder and search options → Folder options → View tab → Show hidden files and folders. Profile folders are located in: ~/.mozilla/firefox/ The ".mozilla" folder is hidden by default. Profile folders are located in one of the following folders: ~/Library/Mozilla/Firefox/Profiles/ The tilde character (~) refers to the current user's home directory. So ~/Library is /Macintosh HD/Users/ You can use the Open Profile Folder extension, which will open your profile folder if you use the corresponding menu item in the "Tools" section. It is not recommended to edit these files directly. Instead, use the user interface. The exceptions are three files whose name starts with "user". They are meant to be edited by the user directly. For more information about files, please refer to the table below. Are multiple people using the computer? Problems with the browser, but reinstalling it is undesirable? The program says that your profile could not be loaded? In all these cases, there is only one way out - to create a new Firefox profile without deleting the old one. Today we will tell you how to do it and give a couple of tips. First you need to find the program's shortcut. It can be located on the desktop, in the taskbar, or in the start menu. Open the properties of the shortcut, switch to the "Shortcut" tab and pay attention to the "Object" field there. Here you must insert a space after the quotes, and after it add -p -no-remote as shown in the screenshot: Thanks to this, every time you start Firefox, the profile manager will begin to appear. From it you can create a new one, select and load an existing one, and delete a profile if it is not needed. This is how the manager looks like for the author of this text, who works with several Firefox profiles at once: Your original profile that you've been working with all this time is called default. Most likely, unlike the picture above, you will only have him in the list of available profiles. Without deleting it, you can create another completely clean Firefox profile. The "Create" button is located to the left of the list of profiles. Creation is very fast. In the first window you will be told the theory: A profile is where all of your data, additions, and changes you made to the original Firefox are stored. These are bookmarks, passwords, plugins, extensions, changed options and much more. In the second window, you will be prompted to give the profile a name and choose where it will be stored: One can agree with what is proposed without changing anything here. The existing "default" profile and the created "Default User" will be isolated from each other. Then just click the "Finish" button and your clean new profile will be ready: Highlight it and click the Launch Firefox button to download a clean version of the browser. In this case, all your data will remain untouched and will be in the “default” profile, which you can also open using the same shortcut by selecting it in the profile manager. By the way, if necessary, nothing prevents you from opening both of these profiles at the same time. You will get two Firefox windows, but not simple, but independent of each other. Each with its own settings and data. As a result, running multiple Firefox profiles is not difficult at all: In the previous section, we explained what to do if Firefox won't start and gives you an error message stating that the profile could not be loaded (missing, not available, not found). As you understand, in this case, you just need to create a new clean profile. However, the question immediately arises about the former, because your, possibly valuable data, remained there. The folder with the old profile could somehow be completely erased. If the profile is deleted, this is a very bad option. However, the situation can be a little more optimistic: for example, only some files were damaged. The folder, in turn, could not be deleted, but renamed or moved. Hence the profile error. You should find the directory where Firefox stores profiles. Open the browser (since we have a new clean profile, it should now at least start), click on the main menu, go to the "help" section, find the item "information for solving problems" there: Clicking on it will open a new tab with various information about the browser, and at the bottom there will be a link button to the current profile folder: After clicking on it, the explorer window will start, where all the information of your current profile will be displayed. In order to see all available profiles, you need to go one level up to the Profiles folder (click on the button indicated by the arrow in the screenshot above). As a result, you will be taken to the directory where folders with Mozilla browser profiles are stored. Each folder here is a profile. We have seven of them, you are unlikely to have more than two: The folders start with a random set of characters, but when the name ends, it's easy to identify them. The Default User is our blank profile (unless, of course, you chose a different name for it during the creation process in the previous section). But default, highlighted in the screenshot, is the original profile, in which something could be saved. All profiles have the same files, by manually copying or moving them with a replacement, you can move your data from one profile to another. Perhaps the most important are three types of data. Actually, for clarity, here are some of the files listed above in one of our test profiles: Having made these replacements, you have a chance not only to reanimate Firefox with a new profile, but also to transfer data from the old one to it. If you are an inexperienced user, we advise you to manually backup everything that you will move and replace somewhere. Well, quite obvious advice: be guided by the size. The larger places.sqlite and sessionstore.jsonlz4, the more of your bookmarks and tabs they store. The new Firefox profile can help you out in many situations. For example, when serious problems arose with the browser, but, and even more so, reinstallation is undesirable. Another obvious use case for Firefox profiles is using them for different versions of the browser. Let's say you are a web developer or just an enthusiast who, in addition to the stable version of Firefox, uses outdated and, on the contrary, new test versions on the computer: For each of them, you can and should make a separate profile. Using one for all is a bad idea. Firstly, the icons on the browser toolbars will be shuffled after the launch of the old versions with the Australis interface and the new ones with the Photon interface. But these are trifles. But, secondly, downgrading is not recommended by Mozilla itself. For example, if one profile has already loaded with a fresh test version, it is not recommended to run it on an older one. Especially if this is not a pure test profile, but your main one. Twice recently, in versions 55 and 58, Mozilla warned that it was making some changes that could cause profile incompatibilities. As a result, it is better to create a separate profile for each version. For the program, by the way, creates it automatically. The rest you can do yourself: It's very fast. The only inconvenience: each time you open any version of Firefox, you will have to manually select the desired profile from the list of available ones. This can be fixed by inserting in the properties of each shortcut the name of the profile that it should run by default: For example, we did this for the beta version of Firefox, whose profile we simply call beta. The name is inserted between -p and -no remote without the leading hyphen and quotes. This concludes our material. After reading it, you can easily create multiple profiles for one version of Firefox, or provide each version of Mozilla's browser with its own independent profile:Windows 2000, XP
Windows Vista and Windows 7
*nix
MacOS X
Finding a Profile Folder
Create a profile
Files and folders in the profile
Folders
Folder Firefox version Description
bookmarkbackups 1.5 and up The last 5 copies of the bookmark file. Updated daily.
Cache Below 1.5 Cache of files downloaded from the Internet. Note: Only profiles in Firefox 1.5 and above? created in non-standard locations in Windows include the Cache folder. For information about the location of the cache, use the about:cache command.
offline cache 3.0 and above Second disk cache for offline file storage. Note: Only profiles created in non-standard locations on Windows include the OfflineCache folder. For information about the location of the cache, use the about:cache command.
chrome
To store userChrome.css and userContent.css files
extensions
Installed add-ons.
microsummary-generators 2.0 and above Generated microsummaries.
minidumps
For the error reporting tool.
preferences
Contains the existing-profile-defaults.js file.
search plugins 1.5 and up User-installed search plugins.
Files
Name Firefox version Description
.autoreg
Temporary empty file signaling a change in installed extensions
.parentlock (Mac OS X)
See parent.lock
blocklist.xml 2.0 and above Automatically loaded list of dangerous extensions
bookmarks.bak Below 3.0 Backup copy of the bookmarks.html file
bookmarks.html Below 3.0 Bookmarks (menu Bookmarks → Manage bookmarks)
bookmarks.html.moztmp Below 3.0 Temporary bookmark file. If you find it, remove the read-only attribute from it, as this results in a lot of bookmark files with names like bookmarks-n.html (Bug 157152)
bookmarks.postplaces.html 3.0 (prerelease) Bookmark file backup in 3.0 Beta 4 and below and 3.0 nightly builds up to 3/14/2008. Not used in later 3.0 builds
bookmarks-(date).html in bookmarkbackups folder Below 3.0
bookmarks-(date).json in bookmarkbackups folder 3.0 and above Daily copy of the bookmark file
cert8.db
Security certificates (menu Tools → Options → Advanced → Encryption → View certificates). If you have problems with certificates, delete this files. See also key3.db and secmod.db
cert_override.txt 3.0 and above Stores certificate exceptions specified by the user
compatibility.ini
Stores the version and path of the last application this profile was used with. When loading a profile with an application that has a different version or path, the XPCOM component registration process starts. This file can be deleted manually - it will be created automatically when you download the application
components.ini Below 1.5 It lists extension folders that have XPCOM components. Replaced by extensions.ini in 1.5
compreg.dat
List of registered XPCOM components. Automatically regenerated when starting the XPCOM registration process
content-prefs.sqlite 3.0 and above Page customization
cookies.sqlite 3.0 and above
cookies.txt Below 3.0 Contains all your saved cookies (menu Tools → Options → Privacy → Show Cookies). Deleting this file will delete all your cookies
cookies.txt.moztmp Below 3.0 Temporary cookie. If you find it, either remove it or remove the read-only attribute from it, as this will create a lot of files with names like cookies-n.txt (Bug 257288)
defaults.ini Below 1.5 It lists extension folders containing files with default values. Replaced by extensions.ini in 1.5
downloads.rdf Below 3.0 Download manager database. Contains a list of all uploaded files. May be removed to resolve issues with slow file uploads or Firefox freezing (Bug 159107)
downloads.sqlite 3.0 and above Download manager database. Contains a list of all uploaded files
existing-profile-defaults.js in preferences folder 2.0.0.2 and higher Overrides default Firefox settings. This file was used to prevent the default settings for existing profiles from being changed when the default search plugin was changed from Yahoo! on Google in Firefox 2.0.0.2 in Japan, China, Korea and Taiwan. Can be removed to restore the latest default settings
extensions.cache
Cache of installed extensions. It lists the installed extensions, their IDs and the folders they are installed into, as well as the date they were last modified. It is used, for example, to register extensions installed by copying to a folder, which is one of the extension installation locations recognized by Firefox. This file is regenerated automatically and can be deleted in case of problems with extensions
extensions.ini 1.5 and up List of folders with installed extensions and themes. The file is generated automatically by nsExtensionManager and is used by low-level code to determine the chrome packages and XPCOM components provided by installed extensions. This file can be removed in case of problems with extensions
extensions.rdf
Information about installed extensions. This one can be removed in case of ghost extensions, as well as in case of problems with extensions
extensions-startup.manifest alpha 1.5 Cache of installed extensions. This file was used in the Deer Park alphas and was later renamed to extensions.cache
formhistory.dat Below 3.0
formhistory.sqlite 3.0 and above Contains a database of saved form data
history.dat Below 3.0 Browsing log: contains a database of all visited web pages (Browsing log menu). This file can be removed in case of problems.
hostperm.1 Below 3.0 Contains a list of sites that are allowed or denied to set cookies and that are allowed to open pop-up windows
key3.db
Key database for certificates (menu Tools → Options → Advanced → Encryption → View certificates). If you have problems with certificates, delete this file. When loaded, it will be recreated with default settings. Existing certificates will be removed and must be reinstalled
kf.txt 2.0
Database of keys for the operation of the anti-fraud mechanism (phishing)
localstore.rdf
Stores the location and size of windows and toolbars defined by the user. If you have problems with windows, delete this file
localstore-safe.rdf 1.5 and up A special version of localstore.rdf used in safe mode to set window and toolbar settings to default
lock (Linux)
See parent.lock
mimeTypes.rdf
Specifies the actions to be taken when certain types of files are loaded. Can be removed to reset settings when uploading files to their defaults
parent.lock (Windows)
Created when Firefox starts with this profile and indicates that the profile is in use. Can be removed to unlock profile
permissions.sqlite 3.0 and above Database with permissions to set cookies, open pop-ups, download images and install add-ons
persdict.dat
Personal Spelling Dictionary
places.sqlite 3.0 and above Bookmarks and History
places.sqlite-journal 3.0 and above Temporary storage for updates to the places.sqlite file when Firefox is open
pluginreg.dat 3.0 and above Registering MIME types for installed plugins. Previously located in the Firefox folder containing profiles
prefs.js
All Firefox settings (see about:config)
search.rdf Below 2.0
search.sqlite 2.0 and above Information about your search plugins
secmod.db
Database of security devices (menu Tools → Options → Advanced → Encryption → Security devices)
sessionstore.js 2.0 and above Saved Sessions
signons.txt Below 1.5.0.10, Below 2.0.0.2 for 2.x branch Encrypted saved passwords (menu Tools → Options → Security → Show passwords). Requires key3.db file to work
signs2.txt Above 1.5.0.10 for branch 1.5.x, Above 2.0.0.2
signs3.txt 3.0 and above Encrypted saved passwords (and exceptions for sites that have "Never save password" selected) (menu Tools → Options → Security → Show passwords). Requires key3.db file to work
signons.sqlite 3.5 and above Encrypted saved passwords (and exceptions for sites that have "Never save password" selected) (menu Tools → Options → Security → Show passwords). Requires key3.db file to work
urlclassifier.sqlite or urlclassifier2.sqlite or urlclassifier3.sqlite 2.0 and above Anti-Phishing Data File
urlclassifierkey3.txt 3.0 and above Anti-Phishing Key Database
user.js (does not exist by default)
User defined configuration file. The values from this file will be overwritten in the pref.js file when Firefox starts. The main difference between the user.js file and pref.js is that Firefox cannot change the values set in user.js - only the user can do this
userChrome.css in chrome folder (doesn't exist by default)
User-defined CSS rules for changing the appearance of an application.
userContent.css in chrome folder (doesn't exist by default)
User defined CSS rules designed to change the appearance of web pages
userChrome.js in chrome folder (doesn't exist by default)
User-defined JavaScript code to change how the application works
webappsstore.sqlite 2.0 and above DOM storage
xpti.dat
List of registered XPCOM interfaces. Automatically re-generated when starting the XPCOM registration process
XUL .mfasl (Linux)
See XUL .mfl
XUL .mfl (Windows) Below 1.5 Cached user interface data. May be removed to resolve issues. Note: In Firefox 1.5 and higher, only profiles created in non-standard locations on Windows include a XUL .mfl file. For information about the location of the file, use the command about:cache
XUL FastLoad File (Mac OS X)
See XUL .mfl
Files and folders outside the profile
Name Firefox version Description
crash reports 3.0 and above Crash files for Breakpad
Desktop Background.bmp (Windows) 1.5 and up Desktop background image set by Firefox. The file is created when you select the "Set as desktop background..." item in the context menu.
pluginreg.dat Below 3.0 Registering MIME types for installed plugins. In 3.0 pluginreg.dat is located in the profile folder.
profiles.ini
Contains profile location information. Can be edited to refer to a moved profile. If this file is deleted, then the next time you start the program, it will be regenerated along with a new default profile.
registry.dat
Contains information about the location of the profile in older versions of Firefox (no longer used).
How to create and download a new Firefox profile
Where are Firefox profiles located
Transfer files between Firefox profiles
Firefox profiles and versions
