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about:config configuration export

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Can the about:config file be exported on a Mac OS running high sierra for comparison purposes?

I can open about:config but can't seem to copy or export the values.

Can the about:config file be exported on a Mac OS running high sierra for comparison purposes? I can open about:config but can't seem to copy or export the values.

All Replies (13)

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No, there is no way to export all settings shown on the about:config page and there are also hidden prefs that have an assumed default value and will only appear when you would create them. Firefox stores the user set (bold) prefs in the prefs.js file in the profile folder.

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The ability to save or export the configuration of about:config and preferences to transfer configurations of FF to other workstaitons would be an excellent feature.

Can anyone suggest any reason it doesn't exist?

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Exporting all prefs wouldn't make sense because a lot of prefs are profile dependent and wouldn't work in another profile and a other prefs store time stamps as you can see if you order the about:config page by Status to get modify prefs at the top. We never recommend copying a file like prefs.js to other profiles. You can look at prefs.js and decide what prefs you would want to backup and copy these to a text file. Preference settings are only for internal use, hence the warning that is displayed when you open this page.

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Absolutely exporting about:config and preference settings would make sense.

1. A client who has more than one FF browser on different workstations could ensure consistency between all browsers.

2. If any modifications are made a comparison of the configuration can be made.

FF may not be able to perform this function currently but I will make a suggestion to feed back June-1-2019.

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You can use Sync to sync some selected prefs among profile.

  • prefs that have a corresponding services.sync.prefs.sync.<pref-name> pref that is set to true will be synced to other devices
  • prefs that have a corresponding services.sync.prefs.sync.<pref-name> pref that is set to false will be excluded from syncing
  • if you want to sync prefs that are currently not included then create a corresponding Boolean sync pref and set its value to true
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This is more than syncing. This is for an administrator to view alterations in the configuration of FF.

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You can lock prefs via an autoconfig file if you do not want users to change them or if you want to enforce a specific configuration.

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My main concern is how can I confirm the configuration of a FF configuration compared to other FF I may have on other operating systems like linux Apple or windows.

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You can compare the prefs.js. All prefs that aren't the default have their values stored in prefs.js. Note that some prefs are platform specific and do not appear on other platforms (e.g. Windows Media Foundation media wmf prefs) or can have a different default value. Prefs that store a time stamp as their value also can't be compared because these pref continuously change. You can make a list of important prefs and use this list to scan a prefs.js file and possibly create a new file with only these user_pref() lines.

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The pref.js contains more than the configuration of FF There is also more than one pref.js on my Mac OS running high sierra.

The recommendation I sent on June-1-2019 is for a export of FF configuration which only includes changes made to about:config and preference changes.

You mentioned that pref.js is platform specific which is not of any purpose to knowing the configuration of FF.

Here a partial example of my pref.js it has items that are not part of the configuration of FF but the operation of FF.

// Mozilla User Preferences

// DO NOT EDIT THIS FILE. // // If you make changes to this file while the application is running, // the changes will be overwritten when the application exits. // // To change a preference value, you can either: // - modify it via the UI (e.g. via about:config in the browser); or // - set it within a user.js file in your profile.


user_pref("browser.migration.version", 80);

user_pref("browser.safebrowsing.provider.google4.lastupdatetime", "1559947191673"); user_pref("browser.safebrowsing.provider.google4.nextupdatetime", "1559948965673"); user_pref("browser.sessionstore.upgradeBackup.latestBuildID", "20190504212614");

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mace2 said

The pref.js contains more than the configuration of FF There is also more than one pref.js on my Mac OS running high sierra.
...
Here a partial example of my pref.js it has items that are not part of the configuration of FF but the operation of FF.

You should find exactly one prefs.js file in each profile.

The items you mention are considered "modified" in about:config, so prefs.js and about:config are consistent in that regard. Obviously a lot of those are not important for configuring Firefox. However, I don't know who has the patience to sit down and write a filter for the file. Perhaps you?

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For the troubleshooting information page there is a PREFS_WHITELIST filter available for including some pref branches.

  • resource://gre/modules/Troubleshoot.jsm
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That does not solve the issue. There are values that do not involve the configuration of FF. Also the file is not the same for all O.S.'s