New Windows 11 has different UI elements for the windows as Windows 10. For example the shadows are wider, gray and it seems the windows is "flying" over the desktoop. The new Office 2021 shares this design in Windows 11.
If I use the Infragistics Thema "Office 2013" then the app sees not belonging to a new design with short and very contrast black shadows. It is immediatily visible and sees very old-facioned in Windows 11.
We need a new theme for xamRibbonWindow which has the same new visual and design elements as new Office 2021 in Windows 11.