I did a dump of the tags available for the validate_user form and there's a tag named user. What is that tag for?

Reason I ask is I need to be able to tie the user to the validation form. I have a global that calculates how old a person is and I thought it would be easy to just use that global tag on the validate form (essentially hiding the validate form if they were under 13 and enabling it if they were 13 or older).

Thanks,
Kevin

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