How to rotate videos with ffmpeg

Pontifications

Usually it’s just the metadata!
from SO:Rotating videos with FFmpeg, here’s how to change the metadata from 90 to 0

ffmpeg -i ~/Downloads/45620789954.mp4 -map_metadata 0 -metadata:s:v rotate="0" -codec copy 16dec2018-cypress-powerline-xc-rotated.mp4 # preserves metadata