Badge in a tab?

Hi,

is there a yml syntax to put a badge in a tab?
I do see this lab example but it seems this is vue/html: https://lab.getkirby.com/public/lab/components/tabs

Thanks

Mark

My non-working approach:

 'tabs' => [
            // Tab 1: My Lessons (Filtered to trainer's lessons)
            'tab_lessons_readonly' => [
                'label' => t('panel.club.myLessons', 'My Lessons'),
                'icon'  => 'calendar',
                'badge' => 5,
                'theme' => 'warning',
                'columns' => [
                    [
                        'sections' => [
                            'lessongroups' => [

No, this is not available from a blueprint, and I’m not sure that this would make sense, given that the badges are used to indicate changes in a tab:

Thanks Sonja again for the quick response.

I understand your remark, there are other ways to indicate some arbitrary values.
I just wondered if the badges could be defined in yml/php.
You provided the answer (:-

Regards!