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I have a few question about the relays.
When I cross post, it gives me the option of relays (optional).

If I'm not specific, where does it get published to?

What if I only want to publish to certain relays?

If you click on the little i icon this is what it says which I think answers your question:

https://m.stacker.news/30791

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I see, so there's no way to be just publish to just a specific relay(as it's paid) and not public like the rest? like can you fix this option?