Can I use subprotocol with Sec-WebSocket-Protocol in header?

[ddotx]

I want to use it for the connection with AWS AppSync. I can connect to AppSync with Postman by this header
Sec-WebSocket-Protocol: graphql-ws
on URL likes
wss://example1234567890000.appsync-realtime-api.us-east-1.amazonaws.com/graphql?header=xxx&payload=e30=

and on my module I set

const link = ApolloLink.from([httpLink.create({ 
   uri: URL,
   headers: new HttpHeaders().set(
       'Sec-WebSocket-Protocol', 'graphql-ws'
   )
})]);