Implement an API for scaling the content of the Popup control. When scale is set the position of the control based on its target should not be affected. The HorizontalOffset and VerticalOffset should also be preserved. Also, introduce a scale API for all controls that internally are using Popup - like ComboBox, AutoComplete, Pickers etc.

It would be nice to have more animation styles when the popup opens/closes.  Specifically, it would be nice to have an animation that slides in from a direction (top, bottom, right, left).  I would like to have a popup that appears to slide up from the bottom of the page when it opens and slides down when closing.  I know you can get a similar effect with the SideDrawer control but would prefer to use the popup.

The issue can be reproduced with ComboBox, AutoComplete or Pickers - when placed inside a Popup, the dropdown is not positioned at the expected position.

Provide a way to blur the background of the popup, so that the user cannot see through it.

The Popup is not correctly positioned on Windows when changing the size of the window by Minimize/Maximize. 

Currently when the user taps outside the non-modal popup, the popup is dismissed. We'd need to provide a way to set focus to input fields in the page without removing/closing the popup.

When the Popup control is attached to the page, the "Top" and "Bottom" options of the Placement property does not respect correctly.

When popup is opened and from it navigate to a new page, the popup does not close and stays open on the new page. 

If I double click on Button (popup is attached to this button and opens on a button click) ->  in macOS, iOS, Android, the Popup opens and then closes. While in Windows, the Popup is still open.

When opening a modal page when using Shell.Current.PushModalAsync, on iPad the popup inside this page is not centered, partially cut or not visible at all. It works on Android, iPhone, MacCatalyst and WinUI.

When adding for examples, ComboBox/AutoComplete, Pickers inside RadPopup and open the pickers/combo dropdown. Then close the RadPopup, the popup of the pickers/combo/autocomplete stays open. The behavior occurs on iOS, MacCatalyst and WinUI. On Android exception is thrown.

Popup:

Calling

IsOpen = true,
IsOpen = false,
IsOpen = true,
IsOpen = false,

while the last IsOpen update isn't ready, kills the Popup.
It works async, even if animations are set to none/0s and there is no public event to validate the last update is fully done (Popup opened/closed)

In my case i have a popup opened, while a search operation is running in the background.
If this background search returns too fast and i set IsOpen to false, the update is ignored and the popup keeps in an opened state.