Firefox has a lot of cool hidden features that you guys don't want enabled by default for reasons and are only accessible in about:config (which is unfriendly).
You could add an option "Show advanced settings" that would add a new section in browser settings the same way "Firefox Experiments" does.
Except that this one could be enabled without having to go in about:config, otherwise it would kill all the purpose.
In that section you would expose select settings people are often asking for without knowing they're already there.
To name a few I'm personally using :
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