Vlc-record-2021-05-24-16h17m26s-index-dvr.m3u8-... -

If you are tech-savvy, pass the file through FFmpeg using the command ffmpeg -i input_file -c copy output.mp4 . This will attempt to take the raw video data and place it into a healthy MP4 container.

To understand why this happens, we can look at the anatomy of the file name itself: vlc-record-2021-05-24-16h17m26s-index-dvr.m3u8-...

VLC is highly forgiving. Drag and drop the file directly into VLC. If it was a raw data dump, VLC might still be able to read the video frames. If you are tech-savvy, pass the file through