Mozilla added an option to the about:config page of Firefox Stable that allows users to list only modified preferences
This is cool, but I’m not sure how much value it provides. For example app.update.lastUpdateTime.browser-cleanup-thumbnails counts as modified even though I never modified it. I understand that it was modified by the browser but it would be nice to see which preferences I have changed from the default so that I can possibly reset them if I don’t think I need that modification anymore. As it is most of this list is stuff that is normal or even expected to be modified and the default isn’t the “recommended” option.
They patched this in because people complained about this going missing when they removed the ability to sort columns in about:config (beforehand you could “sort” the modified-column to have all modified fields appear at the top).
So, while you’re right, that’s probably more effort than they really wanted to put into this.
And if you do want to keep track of your modified about:config-preferences, you might rather want to keep them in a user.js-file anyways: http://kb.mozillazine.org/User.js_file
That way, you can also put it into version control and easily apply it to new Firefox installations.
I hope they’ll also backtrack on their idea of disabling about:config on Firefox Stable for Android eventually.
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