<f:FLoatableWindow
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:f="clr-namespace:System.Windows.Controls;assembly=FloatableWindow"
<f:FLoatableWindow
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:f="clr-namespace:System.Windows.Controls;assembly=FloatableWindow"