Add closed captions in both past streams and live streams
So not just people who dont have any disabilities can watch I bet you guys and girls that even people with disabilities want to watch you stream. even deaf people but they dont know what the gamer is saying so why not let them take part in 100% of the stream and not half of it because they don
t know what the gamer is thinking. It will get you more customers and I know every company wants more customers.

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Ollee64 commented
Past streams is kind of easy to do, in the grand scheme of things, and I think hasn't been done yet because up until now Twitch has largely focused on the LIVE interaction inherent in their platform.
Current live streams is a different beast. I would LOVE to see this feature added, as it's part of my personal wish list(not because I need them, but because I believe as a matter of principle that everyone should be able to find entertainment in Twitch) but there are some technical hurdles present. Every few months something pops up on the subreddit about this, and I can't find the specific thread I'm thinking of because it had a lot of insight from one of the Dev's but here are few relevant threads.
https://www.reddit.com/r/Twitch/comments/2vh3cc/its_time_for_twitchtv_to_implement_live_captioning/
https://www.reddit.com/r/Twitch/comments/4f75zd/complete_video_guide_for_obs_studio/
https://www.reddit.com/r/Twitch/comments/5k7ajm/obs_studio_1700_released_replay_buffer_windows/ -
kbwolfe commented
Add subtitles to past broadcasts so people who are deaf or hard of hearing can enjoy twitch too. I would say add them to current streams, but I'm not sure if that can be done or would cause more delay. Still, I would like to be able to read what is being said so I don't have to miss out on half of the stream.