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Hi everyone :) I created my pref.js which is customization of my about:config settings. As I found, just those keys and values are stored in pref.js that are changed and not in default state, not all. OK then I inserted settings that are modified into pref.js like browser.startup.page;0 Now, it's OK, the question is: With the major changes made both in UI and code of Firefox, with each new build, how can I check my pref.js to see if some properties are added / changed state / removed so I can update my pref.js with each new version? Any idea or suggestion? Thanks

Hi everyone :) I created my pref.js which is customization of my about:config settings. As I found, just those keys and values are stored in pref.js that are changed and not in default state, not all. OK then I inserted settings that are modified into pref.js like browser.startup.page;0 Now, it's OK, the question is: With the major changes made both in UI and code of Firefox, with each new build, how can I check my pref.js to see if some properties are added / changed state / removed so I can update my pref.js with each new version? Any idea or suggestion? Thanks

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I don't know if anything is available like that, but Go to the Mozilla Add-ons Web Page {web Link} (There’s a lot of good stuff here) and search for what you want.


One thing you can do is to Copy your Firefox profile to another location on your hard drive. There are 3rd party programs that can scan two different files and report any differences.

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Maybe consider to use a user.js file to initialize a new profile. You can rename/remove user.js once it has done its job to initialize specific prefs.

The user.js file is processed each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

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I suggest keeping frequent backups, then you can do a file compare to see what's different.