doesn't work in druadmin theme

@Yan2020 when a theme doesn't work with this module it is typically because their block templates don't include the standard title prefix/suffix as seen in the core block module's base template:

  {{ title_prefix }}
  {% if label %}
    <h2{{ title_attributes }}>{{ label }}</h2>
  {% endif %}
  {{ title_suffix }}

This module relies on those inclusions, which was a very big improvement on the previous method the module relied on to target blocks using CSS targets. You have two options:

1. Create a sub-theme of the druadmin theme and create your own block template(s) that implement the title prefix/suffix.
2. Contribute a patch to the druadmin theme that implements the title prefix/suffix in the block template(s) in that theme and use a patch of that contribution in your own project (recommended).

Marking this issues as Support Request since the issue lies outside this module. I will keep this open for at least a month to allow for further discussion.