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modified default preferences do not load properly(untill firefox is reset)

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  • 2 have this problem
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  • Last reply by stewievader

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i am trying to modify some of the default preferences loaded by firefox , using https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/A_brief_guide_to_Mozilla_preferences (changing defaults section).

however after adding the file they will not load unless firefox is reset, though this should be necessary. same thing happens on a new profile until firefox is reset on there aswell

how do i get firefox to load these modified default preferences without having to go and reset firefox on every single user account.

i am trying to modify some of the default preferences loaded by firefox , using https://developer.mozilla.org/en-US/docs/Mozilla/Preferences/A_brief_guide_to_Mozilla_preferences (changing defaults section). however after adding the file they will not load unless firefox is reset, though this should be necessary. same thing happens on a new profile until firefox is reset on there aswell how do i get firefox to load these modified default preferences without having to go and reset firefox on every single user account.

Modified by stewievader

All Replies (4)

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no i can save preferences just fine whether its in the default options menu or about:config.

the problem is when i place an all_xxxx.js file with modified default preferences in (install_directory/defaults/prefs/) Firefox does not load these modified pref's unless i use reset firefox under troubleshooting information. once i do that it loads the file just fine,but has to be done for every user account

since im unfamiliar with this its possible i misunderstood/messed up something, so heres a copy of that js file

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Files placed in /defaults/prefs/ are only copied to a newly created profile, so this behavior is to be expected.

If you want to modify prefs directly for all profiles then you need to use a mozilla.cfg file in the main Firefox program folder.


Use a mozilla.cfg file in the Firefox program folder to lock prefs or specify new (default) values.

Place a file local-settings.js in the defaults\pref folder where you also find the file channel-prefs.js to specify using mozilla.cfg.

pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0); // use this to disable the byte-shift

See:

These functions can be used in the mozilla.cfg file:

defaultPref();  // set new default value
pref();         // set pref, but allow changes in current session
lockPref();     // lock pref, disallow changes

Modified by cor-el

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thanks,then that article needs to be changed...it states that it applys over new and existing profiles.