Let extensions submit events to EventSub, mimicking rewards
I started researching how to make a Twitch extension, and for the life of me I cannot find any capability to submit events to be listened to by clients through EventSub (or PubSub).
Being able to do this would relieve simple extensions from having to rely on their own hosted server, but could instead rely on the transports Twitch already provides.
At least with EventSub this seems like a reasonable connection, as it would be a specific subscription, meaning events from extensions wouldn't show up unless specifically asked for.
I believe this is not possible today as there is no subscription that fits it for EventSub and I cannot find anything in the documentation that would suggest the capability exists for extensions.
I'll describe what I want to make with this. My streaming suite allows for screenshots to be captured, and it is quite time sensitive and during things like boss fights it gets spammed. There are other things like mod actions to kill what is said on TTS if it's a bad message, also time sensitive.
Due to this, I would love to make an extension that allows for buttons that trigger events the suite could listen to with low latency. Right now I would have to roll my own backend, then poll it frequently to get any new activations the extension has submitted.
If we could submit activations over EventSub instead, it is simply a matter of subscribing to another subscription to get those events, with a low latency, and no need to host a separate server or roll that backend. It is also lower latency in two ways, there is no polling as we have direct Websocket (or webhook) messages, and there is no additional step using channel points like when using rewards. Or typing out a chat command, which also spams the chat if it's frequently used.