Disabling Forward Button

Disabling parts of the user environment is generally done to hide some bad design at the server side. And that is not a good practice.What exactly is going wrong? What should be fixed? Do you want to prevent the POST being re-submitted?

Implement a POST-Redirect-GET pattern. After finishing the processing of the POST, but right before sending any response, do a redirect to the same URL.

That's a pity then.