I have an HTTP Proxy asset with url rewriting turned on. I have a checkbox that needs to be unchecked for certain things to work in the page that is proxied. When I check it and post (with method GET), the form is returned with an error message as it should be. When I uncheck it and post again, webgui treats it as though it's still checked. Accessing the proxied page directly does not produce this behavior. I noticed that in the URL bar there are two places where the GET data are displayed: once as normal GET URI arguments, and once with HTTPProxy_ prefixes. In the latter, the checkbox is gone when it is unchecked; in the former, it is still there.