MaterialDesignEmbeddedDialogHost and focus on open

When using DialogHost in a Style="{StaticResource MaterialDesignEmbeddedDialogHost}" configuration, then when opening, the focus for the first focusable control doesn't seem quite right.
It can be replicated using dialoghost Sample 2 "pass view".

If I use the embedded version, then nothing seems to have focus.
If I add FocusManager.FocusedElement="{Binding RelativeSource={RelativeSource Self}}" to the first button in embedded a dialoghost:

However I can't just hit enter on that button and there's no dashed lines in the button like this either:

Which seems related to it setting logical focus, but not physical focus: https://docs.microsoft.com/en-us/dotnet/framework/wpf/advanced/focus-overview#logical-focus

Reproduisez le problème avec DialogHost Sample 2, « pass view », en utilisant le style MaterialDesignEmbeddedDialogHost. Comparez le comportement du focus lors de l’ouverture de la boîte de dialogue intégrée, y compris l’activation au clavier et l’indicateur de focus visible ; le travail est considéré comme terminé lorsque le premier contrôle pouvant recevoir le focus reçoit le focus physique et que Enter l’active.