Quoted By:
smplayerfag here
It took me an hour, but I figured out how to get twitch captions in smplayer. I tried opening the stream in mpv alone and they worked fine, but I noticed they populate in later once detected. smplayer doesn't notice this update thus never sees it.
After tearing my hair out for said hour trying a million options in ytdl, mpv, and smplayer the golden option came to light:
>--sub-create-cc-track=yes
This creates the subtitle track ahead of time and it'll populate as soon as it gets it, so smplayer can't possibly miss it.
Now I can shitpost with the best of them. ;~;