When this value is true this Stack will not appear by default in the Stacks Library.
Child stacks used with AddTypes often have no use outside of their parent stack. To reduce clutter and make things simpler for the user you can hide a stack.
Note: Users can choose to show hidden stacks. This is useful for when you have hidden something but the user might need the stack in a very rare circumstance. If you want the stack to always be hidden, you should use Deprecated