Hi, Ingo.
As of v4.4.2 of Event Tickets (ET), from Feb 9, this should have been working as you’re expecting.
I just tested on the latest versions of ET and ET+ and it’s still working as it has been from ET v4.4.2
I believe the issue here is that your WooCommerce email is customized, maybe by your theme or an add-on, in which case we cannot assist here further.
If you need some coding help, you may want to ask your own developer, the theme or add-on developer, or reference our documentation and list of known customizers.
Please let me know how this goes for you.