That’s called a market. You probably mean a market maker, who may buy or sell a security at a market price without an available counter party. Any market can have a circuit breaker. But usually forex doesn’t because the whole point of the market is to provide a way to convert currencies when needed, compared to stock markets where the main goal is to efficiently allocate capital.
There are multi-dealer platforms that abstract this but you are still directly covered by your contract with the partner counterparty.
Most direct api integrations and multi-dealer platforms implement circuit breakers but they aren’t regulated like equities or futures exchanges.
Compare that to the link which is a forex futures exchange which is subject to cftc regulations around circuit breakers.
Perhaps you have some point different to mine but I can’t discern it because to me you are speaking a different language.
The important thing to understand is that circuit breakers as used at nyse or cme or cboe or lse are only possible because you aren’t dealing directly with your counterparty. There is an intermediary.
So perhaps we agree?