Unable to install the XYZ module since it requires the A module When running (right after site install) the drush cim -y command, the following error appears:

Drupal\Core\Config\ConfigImporterException: There were errors validating the config synchronization. in Drupal\Core\Config\ConfigImporter-&gt;validate() (line 728 of /var/www/ifc_test/web/core/lib/Drupal/Core/Config/ConfigImporter.php).
The import failed due for the following reasons:
Unable to install the XYZ module since it requires the YAML
Editor module.
Configuration XYZ.conf depends on the YAML Editor module that will not be installed after import.
Configuration yaml_editor.config depends on the YAML Editor module that will
not be installed after import.

(XYZ is the name of the custom module.)

I have the yaml_editor contrib module physically under modules
There is a dependency declared in the configuration files above
I also added yaml_editor to the core.extension.yml file to make sure it should be installed

Why config importer not enabling the yaml_editor module? I mean, that's what dependency declaration is for. Also, I've got a couple of other modules which are not enabled after site-install, they will be enabled during the drush cim process.
Of course drush en yaml_editor -y solves the problem, however, it's part of a building process, and I don't want to just insert an extra line into deployment script, just because this strange thing is happening.
Any ideas why config management doesn't enable (installs) this dependency, and why it says: &quot;that will not be installed after import&quot;?
Adding the yaml_editor to core.extension.yml solved the issue. 
It perhaps were removed due to a complex git merge, and that's why my install process started to fail all that sudden.