Azure SignalR Serverless (JavaScript) client – sending json body to the negotiate API

Is there any way to send JSON body using JS client SignalR library?

I’m trying to find a way to add JSON body using following JS code

const connection = new signalR.HubConnectionBuilder().withUrl("https://[host]/[path]",
 {headers:{"Authorization": "Bearer [token]","Content-Type": "application/json","Accept": "application/json"
 },transport: signalR.HttpTransportType.LongPolling})
.configureLogging(signalR.LogLevel.Trace)
.withAutomaticReconnect()
.build()

Kind regards

https://learn.microsoft.com/en-us/javascript/api/@microsoft/signalr/ihttpconnectionoptions?view=signalr-js-latest

Cannot find option to provide request body.