If the video has an audio track, the data might be hidden in the sound. Tool: Audacity
The MP4 might be a "polyglot" or have a ZIP/RAR file appended to it. Tool: binwalk Command: binwalk -e 0h8q1ak2acptoechqhoxq_source.mp4
Look for unusual entries in the "Comment," "Description," or "Artist" fields. Creators often hide strings or Base64-encoded text here.
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