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How to backup preferences / options and UI customization ?

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  • 3 have this problem
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  • Last reply by Clairvaux

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Setting Preferences / Options and customizing the UI takes a long time. However, there does not seem to be any obvious way to backup and restore them.

The Refresh function specifically wipes Preferences and Extensions, as we're warned that they are the first suspects when Firefox misbeheaves. MozillaZine says :

"user.js (an optional file) and prefs.js - User preference settings. Not recommended to transfer if you had problems in your old profile. You may need to manually edit the paths in prefs.js to reflect the new profile location."

http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox#Files

I've found a single extension purporting to do that, Save / Load Prefs, but I don't understand how to make it work, and it has one review only.

Let me add an important point : I want to be able to copy Preferences and UI customization across different Firefox profiles on different Windows user accounts, since I have two user accounts, one admin and one non-admin. MozillaZine seems to say you can't do that, unless you manually edit paths in prefs.js, which I find rather risky.

By the way, is the UI customization stored in user.js and prefs.js as well ?

Setting Preferences / Options and customizing the UI takes a long time. However, there does not seem to be any obvious way to backup and restore them. The Refresh function specifically wipes Preferences and Extensions, as we're warned that they are the first suspects when Firefox misbeheaves. MozillaZine says : "user.js (an optional file) and prefs.js - User preference settings. Not recommended to transfer if you had problems in your old profile. You may need to manually edit the paths in prefs.js to reflect the new profile location." http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox#Files I've found a single extension purporting to do that, Save / Load Prefs, but I don't understand how to make it work, and it has one review only. Let me add an important point : I want to be able to copy Preferences and UI customization across different Firefox profiles on different Windows user accounts, since I have two user accounts, one admin and one non-admin. MozillaZine seems to say you can't do that, unless you manually edit paths in prefs.js, which I find rather risky. By the way, is the UI customization stored in user.js and prefs.js as well ?

Chosen solution

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences

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For your second question, I believe the setting in about:config is browser.uiCustomization.state and the data should have "{placements...." in there. I have not tried it before, but this is a good tool:

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Chosen Solution

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences

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The data is not stored in a single file. For example:

prefs.js stores:

  • layout of buttons/controls and toolbars *
  • pinned sites on the new tab page
  • blocked sites on the new tab page
  • most settings on the Options page (not including lists of sites)

xulstate.json xulstore.json stores:

  • which toolbars are turn on/off *

content-prefs.sqlite stores:

  • preferred zoom levels by site
  • last used upload/download folder by site

permissions.sqlite stores:

  • site-specific cookie, popup, extension installation, full screen, location, plugin, and data storage permissions

And numerous others...

* Both assume certain add-ons are present, and may retain phantom controls/bars when those add-ons are removed.

Modified by jscher2000 - Support Volunteer

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@Jeff: I assume you would want to correct this xulstate.json stores: to xulstore.json

Note that sessionstore.js also stores all open tabs including pinned tabs and tab groups.


  • bookmarks and history: places.sqlite
  • bookmark backups: JSON backups in the bookmarkbackups folder
  • SQLite files like cookies.sqlite (cookies) and formhistory.sqlite (saved form data)
  • logins.json and key3.db (decryption key) for Passwords saved in the Password Manager
  • cert8.db for stored intermediate certificates (Certificate Manager)
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite and possibly content-prefs.sqlite for Permissions and Site Preferences
  • sessionstore.js for open tabs and pinned tabs and tab groups
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cor-el said

@Jeff: I assume you would want to correct this xulstate.json stores: to xulstore.json

Thanks for spotting that. Fixed.

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Thank you, gentlemen.

So it seems preferences and customisations really are all over the place, although saving prefs.js would give you something resembling your previous Firefox (most Options, plus layout of buttons and toolbars).

I will try FEBE, which seems to offer everything but the kitchen sink. If it does what it says it does, it's almost too good to be true.

The Automatic Mozilla Configurator seems to do what I want to do, but it looks like programmer's level stuff -- that's too advanced for me.

Any objections to using those tools to restore user data across different Firefox profiles or Windows user accounts ?

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You can backup the browser.uiCustomization.state pref line from prefs.js (or about:config) to have a backup of the toolbar customization. This pref stores the toolbar customization in JSON format. The prefs.js file stores a lot of prefs that are profile usage specific like timers when action were performed and other maintenance data.

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cor-el said

You can backup the browser.uiCustomization.state pref line from prefs.js (or about:config) to have a backup of the toolbar customization.

Nice ! I found it in about:config. What would be the safe way to back it up, then restore it ? I see many options there, and I wouldn't want to break anything.

This pref stores the toolbar customization in JSON format. The prefs.js file stores a lot of prefs that are profile usage specific like timers when action were performed and other maintenance data.

So the browser.uiCustomization.state pref line would be safe to backup and restore across different Firefox profiles or different Windows user accounts, but not necessarily others ?

Modified by Clairvaux