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about:config preferences not changing (macOS)

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  • 2 have this problem
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  • Last reply by cor-el

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Greetings,

I'm trying to change some of the settings in Firefox. This is on a Mac running FF 60.0.2. I've created the mozilla.cfg and autoconfig.js files and added them to the appropriate locations. However when I check in about:config there aren't any changes. For example in my mozilla.cfg file I have lockPref("app.update.enabled", false); but it's not showing as locked in about:config. And I have tried removing the Firefox and Mozilla folders in ~/Library/Application Support. Any suggestions?

Thanks

Greetings, I'm trying to change some of the settings in Firefox. This is on a Mac running FF 60.0.2. I've created the mozilla.cfg and autoconfig.js files and added them to the appropriate locations. However when I check in about:config there aren't any changes. For example in my mozilla.cfg file I have lockPref("app.update.enabled", false); but it's not showing as locked in about:config. And I have tried removing the Firefox and Mozilla folders in ~/Library/Application Support. Any suggestions? Thanks

Chosen solution

Yes, both files need to start with a comment line (//) because this line is skipped for security reasons.

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All Replies (4)

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Did you create the files and then start Firefox? If you created the files while Firefox was running, they would be overwritten.

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save

Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.

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Can you post the locations of the files you used and possibly the full content of mozilla.cfg?

If there is an error in mozilla.cfg then you normally get an error message.


The local-settings.js file needs to be in:

  • /Applications/Firefox.app/Contents/Resources/defaults/pref

The mozilla.cfg file needs to be in:

  • /Applications/Firefox.app/Contents/Resources

See "Changes Over Time" -> "Mac Directory Change"

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I think I may have figured this out after going over this:

https://support.mozilla.org/en-US/kb/customizing-firefox-using-autoconfig

I changed my code to start at the second line and now the preferences appear to be locking.

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Chosen Solution

Yes, both files need to start with a comment line (//) because this line is skipped for security reasons.