It’s basically like frozen rows in Excel – the item will always stay as the first child of the parent list no matter what, even though this is your inbox and you’ve specified to send new inbox captures to the top of the list. So for example, for non-Inbox frozen items stay at top. For Inbox where you have specified new items go to the top, they would be inserted below any frozen items, if they are present.
This would serve as a constant reminder in that context.
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