I have a scenario where I want to open a Popup when user click on "User Registeration" screen, the popup will check for the availability of user id. If user ID already exist then on click of button on popup, the system to take it to "Search User" screen without showing "User Registeration" screen in background i.e. loading of "User Registeration" screen should get cancelled.
Please help how can I implement the same. Also I don't want User "Registeration screen" to be displayes in background of popup, let's say a blank white screen is fine.
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