Clicking the Add 'State button' shows a brief 'Please wait...' spinner then stops without adding a new state row to the form and results in the following php error in the log:
Symfony\Component\Routing\Exception\InvalidParameterException: Parameter "workflow_state" for route "entity.workflow_state.clone_form" must match "[^/]++" ("" given) to generate a corresponding URL. in Drupal\Core\Routing\UrlGenerator->doGenerate() (line 204 of /var/www/drupalvm/drupal/docroot/core/lib/Drupal/Core/Routing/UrlGenerator.php).
Drupal Core 8.9.0
Workflow 8.x-1.4
Both Workflows and Workflow are enabled. Suspect this may have something to do with it. Workflow is required by Workflow Access. Workflows is required by Content Moderation.
Fixed
1.4
User interface
Not all content is available!
It's likely this issue predates Contrib.social: some issue and comment data are missing.
This should now be solved with 🐛 Route "entity.workflow_state.devel_load" error InvalidParameterException with contrib Devel installed Fixed .