Could you clarify what this video is about? It might be one of a few things:
If it's from a specific YouTuber or streamer, I can look up their recent "useful features" lists if you provide the creator's name. 2_3Boobs-liUrfBFV.mp4 ...
If it's a tech demo, the "useful feature" might be a specific software trick or setting. Could you clarify what this video is about