In Event Registration, make it possible on Registrant Forms to have pre-filled ("use current value") Person Attributes only be editable if they are empty/blank. This would help protect against accidental editing of things like birthdates when a parent has mistakenly selected the wrong child. (Or thinking they'd be sneaky and change the child's grade to get them registered for a grade-limited special event with their sibling, which then consequently prevents the affected child from being checked-in to their normal/appropriate classroom on Sunday. That's happened enough times we're submitting this Idea.)
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