The suffix _source is a major clue. In video processing workflows, this typically denotes the —the high-bitrate, uncompressed version before it gets crunched down for streaming.
We’ve all been there. You’re cleaning out an old hard drive or scrolling through a forgotten cloud storage folder when you stumble upon it: a string of alphanumeric gibberish ending in .mp4 . 0h5hyaw6336fkv38rs086_source.mp4
A backup of a reel or story you posted that was saved directly from the app’s internal database. The suffix _source is a major clue