'show_top_item' is not a supported key.

Did you run drush updb? Not able to replicate

Yes, updatedb was running successfully.
Can I provide you any further information to get the issue analyzed?

try this

I was having the same issue after upgrading from 1.0.0 to 2.0.1, even after updating the database. I applied the changes from the merge request as a patch, and that solved it.

Will deploy this tonight when I’m back in front of my computer

Is working fine! No errors anymore.

Thank you for the quick fix and release @smustgrave

Hey, I think there's an issue with the hook_update_N() that was committed. From the docs, it's safe to use

\Drupal::configFactory()->getEditable() and \Drupal::config(), as long as you make sure that your update data matches the schema, and you use the $has_trusted_data argument in the save operation.

(my emphasis)

Thanks!