They are not enabled, all you get is the user title and well if you really need extra space you can use your location to sneak in info.
Signatures were disabled some time ago on this forum and no one really complained, so well it was decided that they weren't needed. (It also keeps the scum away you see, most people who care more about package than content don't stay here long that is)
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Oh and BTW if you have any more questions; the feedback section is made just for that
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