Originally Posted by alarmguy
AS far as others not wanting to "changing anything in About:Config" ... I ask why? That is what Config is for, its simple to do and made to turn off, like a light switch

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I'll take a stab at this:
1) The UI is not anywhere close to being welcoming to those unclined technically.
2) The necessity of entering in values manually in some of the schema is unintuitive for many.
3) The warning about the warranty or whatever is present upon About:config's first access by a user is off-putting and threatening to some.
4) A lot of the technical nomenclature is unfamiliar to a casual or normal user.
People do not want to "configure" their software at all, usually. Users, of course, would prefer that developers read their minds and design the software according to the user's preferences to begin with; but short of that, any customizations that a user needs to make they'd prefer to make within a standard dialog page with buttons or drop-downs described in plain language.
I know that About:config was designed specifically to hide away some elements of the software's configuration - that may impact function and performance - from a casual user's view to avoid confusion and to mitigate a user messing something up. Autoplaying video, in my opinion, ought to be an option to disable that is as conspicuous and easily-accessible as any other "feature".