Could you provide more on where you encountered this filename or what the video is supposed to contain ? Knowing the source or the general subject matter would help in identifying it.

: A video from a personal device (like a smartphone or security camera) where "COAT" might be a default prefix or a specific folder designation.

It does not appear to be a viral video, a known piece of media, or a documented internet phenomenon. This specific filename most likely refers to one of the following:

There is no public information or widely known record regarding a file named .