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It looks like you're asking about a feature related to downloading YouTube videos on iOS, specifically with a reference to "1257 verified." However, there is no official "YouTube download" feature within the YouTube iOS app itself, as YouTube’s terms of service prohibit downloading videos for offline viewing except through YouTube Premium (which uses a proprietary, encrypted format).

This guide provides verified, safe methods to get YouTube running and download videos for offline use on iOS 12.5.7. 1. How to Download the YouTube App on iOS 12.5.7