Feature request: add ability twitch to rewind and watch previous section of the stream while it is streaming

[XingShelly]

Use Cases

After the stream ends you can watch the full VOD no problem. However, during the stream itself you cannot rewind. There are other apps like Xtra that allow you to rewind during the stream. I don't exactly understand the technicalities of how they are able to do it. And usually you need to be a paying member to be able to do it. But somehow I can do it on Xtra.

Proposal

Please add the ability to do so in GrayJay as well, if it's possible.

References

https://github.com/crackededed/Xtra
This is the github repo of the app.