title: How to create a popup in UWP
body: <p>I'm trying to make a desktop application with Width= 600 Height=500.
  How to create a popup dialog that overlaps complete window of the app?
  When the user clicks on Terms&amp;Condition (within mainpage) I want to popup a dialog like <a href="https://ibb.co/b92VkU" rel="nofollow noreferrer">this</a>?</p>