Having a fully free version being put aside just for the sake of
understanding: with youtube-dl and vlc, what data am I giving up by using
that tiny bit of JS used for making URLs readable?
Can't that be sandboxed, so that any extra JS execution would remain harmless
and limited?
Like some kind of filter.
The non-free JS is needed, AFAIK. Either it's translated to a libre JS
replacement and added to avideo, or used as-is, but in a sandbox (Firejail).
Sure it would not be fully free, but it should work regarding privacy.
Obviously that's for a worst case scenario.