Referring to the answers made by the developers in Popups are nice, add an option to have Rounded Corners as that's more appealing and provides a distinct look #352, all you need to do is set the background color of the popup to be transparent.
<toolkit:Popup xmlns="http://schemas.microsoft.com/dotnet/2021/maui" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:toolkit="http://schemas.microsoft.com/dotnet/2022/maui/toolkit" Color="Transparent" x:Class="MauiApp1.NewPage1">
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