Twitch updated their VOD chat replay system so that you can now comment alongside a chat that happened during AND after the stream
So basically you're talking to people from the past who aren't even aware of the you from the present that is talking among them
And there are also other people taking part in this new system, so now there's a chat from the past and a separate chat from the """"present"""" past that is getting jumbled into the chat from the past
And it's a new UI, so Better Twitch TV can't modify it to be in dark mode until the devs update the extension
There's an option to disable the post-stream VOD chat, but it's just a really strange feature