I am looking for the source of data that is used as input to generate the small red progress bar below YouTube video thumbnails like this:
The main reason I'm asking this is because I did a full export of my YouTube data and cannot find the source of this anywhere. The view-history JSON only stores clicks on videos, it tells nothing about view progress.
In my interpretation the Google Takout service claims to provide a full copy of data linked to my Google account therefore if this data is not there then this progress bar is either a 'bluff' created by some sort of algorithm or the Google Takeout service does not provide a full copy of my data. Of course as a third option it is possible that view progress is stored somewhere in the Takeout .tgz and I just missed it.