With the webSocketUrl capability set to true a WebSocket server will be started in the browser, supporting bidirectional communication by using the WebDriver BiDi protocol. When the New Session request has the webSocketUrl capability set to true, and the session starts successfully, the value of the capabilities field in the response will have a webSocketUrl property set to the URL of the WebSocket server.


Requesting the WebSocket URL by setting the webSocketUrl capability to true:

POST /session HTTP/1.1
{"capabilities": {"alwaysMatch": {"webSocketUrl": true}}}
{"value":{"capabilities":{"webSocketUrl":"ws://localhost:9222/session/571f206f-c3fe-794c-9218-77fa89595eb9", [..]}, "sessionId":"571f206f-c3fe-794c-9218-77fa89595eb9"}}

See also