When having the following setup:

        <telerik:RadExpander x:Name="expander">
            <telerik:RadExpander.Header>
                <telerik:ExpanderHeader HeightRequest="40"
                                        Style="{StaticResource stdRadExpanderHeader}">

 

and the style is defined as follow:

 <Style x:Key="stdRadExpanderHeader" TargetType="telerik:ExpanderHeader">
     <Setter Property="IndicatorText" Value=">"/>
     <Setter Property="IndicatorColor" Value="Red"/>

The Style does not apply.

it works with 7.1.0 version