Have an issue by using the Template10 for UWP apps. If i want to display special characters at design time everything seems to be ok. At runtime special characters would not be displayed correctly as you can see in screenshots.
<!-- page header -->
<controls:PageHeader Content="Übersicht">
<controls:PageHeader.SecondaryCommands>
<AppBarButton Click="{x:Bind ViewModel.GotoSettings}" Label="Settings" />
<AppBarButton Click="{x:Bind ViewModel.GotoPrivacy}" Label="Privacy" />
<AppBarButton Click="{x:Bind ViewModel.GotoAbout}" Label="About" />
</controls:PageHeader.SecondaryCommands>
</controls:PageHeader>
For example "Übersicht" -> VisualStudio Designer "Übersicht" -> Runtime "?bersicht"
Designer view
Runtime