about TMyV8Handler = class(TCefv8HandlerOwn)

[salvadordf]

Hi,

JavaScript is executed in a different process than the main browser process. This means that you can't access form variables from JavaScript because windows processes are isolated.

Try sending messages between processes as explained in the JavaScript demos comments.

[salvadordf]

GlobalCEFApp_OnProcessMessageReceived receives an ICefProcessMessage with the message arguments.
You can call JavaScript functions with those arguments or store them in a variable that belongs to that process.
Register an extension to use a Delphi function from JavaScript that uses the values you stored previously.