To set up WebMask with a browser, you need to be able to tell it to use a proxy for http: requests. To find out how to do this, see your browser documentation. If your browser doesn't support this, then you can't use WebMask.
In the browser, you will need to:
Set the http proxy host address to be either your own IP address, or the special value 127.0.0.1 (which always refers to you).
Set the http proxy port to 8080. You can use a different value, and configure WebMask to listen on a different port; to do this change the value in the Port box at the top of the WebMask General properties page. The default is 8080.
If the browser was already using a proxy, then you'll need to remember the host and the port it used. Later you will use these to tell WebMask about this existing proxy.