Comment by radicality

Yeah it’s infuriating. I’m using this tool mp4-merge them which afaik preserves almost pretty much all metadata / tracks. What I do in a bash script is: Find all groups of mp4 files that share same last 4 digits, pass those to mp4_merge, do a ‘touch -r’ to update timestamp of merged file to first file in batch. Has been working great so far.

https://github.com/gyroflow/mp4-merge