Saw this one posted over on Reddit and thought it would be worth adding here mostly due to the quality of footage compared to the usual. Looks like possibly balloons or some kind of debris? Attaching Vimeo link at the top just in case the Reddit link stops working.
Weirdness begins at 0:25s
During quarantine last year I got myself a Nikon P1000 which is a 4k DSLR with a 24-3,000mm zoom lens. The goal was to shoot stock footage of sunsets. I left it running one day capturing the smoke clouds from a very large fire in the Angeles National Forest to the east of Los Angeles. The video starts off with two airplane shots so you can see some sense of scale. I shot this video from Echo Park. The date in the metadata says August 15th but I'm not sure that's the exact date the recording took place. I have uploaded the two shots I got, in their original format from straight off the card: https://www.dropbox.com/sh/ihicx7jkmx7rs99/AADUbayG_kbxmdbt2L2mxOKEa?dl=0