The prefix 2019-12-14 indicates the content was likely filmed or released in mid-December 2019.
While there is no "official guide" for a specific video file, here is the context regarding the content and how to manage such files: 2019-12-14_KATEELIFE - GROUP2.mp4
If the video has sound but no picture (or vice versa), you may need to install the K-Lite Codec Pack (Windows) to handle the specific compression used in 2019-era web video. Storage & Organization: The prefix 2019-12-14 indicates the content was likely