Doesn't work - link "Manage attributes" won't show in layout builder

Problem/Motivation

The link in the context menu won't show: Manage attributes

Steps to reproduce

I've:

1. installed via CLI / composer
2. Activated the module
3. Check the configuration & permission (I'm using it as an admin - all classes / titles etc. in the config are checked
4. The link 'manage attributes' won't show up

I've tried:

• different browser
• logout and in again
• create and place a new block

I found these:
https://www.drupal.org/project/layout_builder_component_attributes/issue... →
https://www.drupal.org/project/layout_builder_component_attributes/issue... →

Nothing helped so far - what else can I do?