I’m currently working on a project that is extending the Playwright Java library. I need to interact with a remote service that injects custom parameters into the WebSocket communication between Playwright and the browser.

I’ve noticed that Playwright’s internally logs these parameters when debug mode is enabled (using the DEBUG=pw* environment variable). However, I need to access these parameters even when debug mode is off.

My current challenge is that:

1. I cannot rely on DEBUG=pw*: It’s might not be available in the user environment.
2. The parameters are not part of the standard messages: They are added by the remote service, possibly during the initial WebSocket handshake or in a non-standard response.

My goal is to find a reliable way to intercept either:

• Raw WebSocket messages: This would allow me to analyze the entire communication, including the handshake, and extract the necessary parameters.
• Specific custom parameters: If there’s a more targeted way to access these parameters for the connectOverCDP request without intercepting all WebSocket traffic, that would be ideal.

My Questions:

• Does Playwright Java offer any built-in mechanism to intercept or access raw WebSocket messages in a production environment (without debug logging)?
• Are there any events or hooks within Playwright Java that would allow me to capture these custom parameters?
• If not, are there recommended approaches for achieving this using techniques like bytecode manipulation (e.g., with Javaassist)?
• I was able to see the required parameters in a format specified here but when I intercepted this, it was discovered that this function itself is not being invoked at all, so is there any external dependency that is listening to the events and displaying them on the terminal?

I’m particularly interested in solutions that are maintainable and performant. Any guidance on best practices or potential pitfalls would be highly valuable.