With today's release of Radzen.Blazor (4.1.1) this should no-longer be a problem if you include the -base.css version of a theme. Now all global styling (scrollbars, selection, font etc.) will happen only if you include the "full" version of a theme e.g. "material.css". If you include "material-base.css" this should no longer happen. We will also update the documentation to reflect that.