When I switched to Fluent theme all RadRibbonButtons direct content was aligned to the left instead of centered as it was previously in Expression Dark theme. The problem is, that ContentPresenter in StackPanel named FirstRowContainer has its HorizontalAlignment property set to Left. I don't know how can I change that to Center and I need your help to fix it. Direct content of buttons is TextBlock displaying Font Glyph. Here is sample code:
<telerik:RadRibbonButton x:Name="buttonLock"
Click="ButtonLock_OnClick"
IsEnabled="{Binding IsUiUnlocked}"
Size="Large"
Text="Lock">
<TextBlock Margin="2"
FontFamily="{StaticResource TelerikWebUI}"
FontSize="24"
Foreground="#00BFE8"
Text="{StaticResource GlyphLock}" />
</telerik:RadRibbonButton>