Source: https://www.youtube.com/watch?v=czCfqZrWgio I first saw the above video (dated Oct 22, 2019) via a low-resolution crop re-post on one of the UFO sites, where it looked even less identifiable. While it was unfortunately filmed in portrait mode, it was still a 4K video, so I downloaded that and zoomed in: Looks like an advertising blimp, but with an odd white panel below it. THe original video said "San Diego", so I did a search for tethered blimps in San Diego: Bingo! There's a tethered blimp over San Diego, with a white panel type thing underneath it. Here's some local news video: https://www.kusi.com/federal-agency-to-conduct-urban-drone-tracking-system-testing-through-friday/ Case closed!