What sort of Form/Window is the Excel 2010 SearchANDReplace Dialog ?

Question

I like the Search And Replace Dialog of Excel 2010. I can enter data, see it replace in the grid behind AND THEN I can edit the data in grid without the Search/Replace Window disappearing/going into background.

The SearchAndReplace Window is not a Model dialog. And it also has not settings like "stay at Top" = true because switching to other open applications the Search/Replace Window with Excel together is going into the background.

What sort of Window is that?

Edit in grid behind but Search/Replace Window stays at top of the application BUT not at top of the operaton system!

public class MainWindow.cs

var window = new Window();
            window.Owner = this;
            window.WindowStartupLocation = System.Windows.WindowStartupLocation.CenterOwner;
            window.Width = 200;
            window.Height = 200;
            window.Show();

Answer 1

In Win32 terminology, it's likely to be WS_POPUP, with its owner set to the top-level Excel window.

Different programming environments have different names for this kind of window. For instance, .NET WinForms calls it an owned form.