Recently we started to work on subscribing to order webhooks topics.
As we worked on it we could not find any reference which describe if orders/updated topic
contains the following topics as well: orders/fulfilled, orders/paid, orders/partially_fulfilled?
What happened when the order financial status change to paid? Is that trigger both the
orders/updated and the orders/paid webhooks or only one of them?
If an order is marked as paid, I would expect it to trigger an update webhook yes - orders/paid would be triggered too. The purpose of orders/paid is more to be able to keep tabs on the payment status without having to listen to all of the other updates too.
I would expect anything that touched the updated_at timestamp on the order to trigger a webhook, but if there's any other specific scenarios you wanted to check up on I'd recommend testing them out.