PushDuplicate

Abstract AS2

@t0 = @pop();
@push(@t0);
@push(@t0);

Adobe documentation

ActionPushDuplicate

ActionPushDuplicate pushes a duplicate of top of stack (the current return value) to the stack.

FieldTypeComment
ActionPushDuplicateACTIONRECORDHEADERActionCode = 0x4C