REST API: supported actions on fulfillment orders

Hi,

USE CASE. There is a fulfillment order with status OPEN, and its supported_actions array is empty (contains no action).

Question is: as this FO supported actions array has not any available action, what will happen if I try to fulfill the item? Will it fail? because I already sent a fulfillment for a FO in this very same use case and the fulfillment was correctly sent.

So the question is: can we send a fulfillment for a fulfillment order event if the ‘fulfillment create’ action is not in the supported actions array? If the answer is no and Shopify API should answer with an error code, could be that the FO is malformed?