The current implementation of pages does not allow you to enter query string directly in the url of a page and we do not have an option for additional url. This is something that we are going to discuss and see how could be implemented. The simplest way to append some query string to the url is using another user control with a single public property where you can set the QueryString on page. The control will add the QueryString with Response.Redirect to the page inside Load event. I agree that this is not a good solution, because there will be always two requests to the page, but this is the simplest way to achieve your goal.
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