CKEditor 5 not working with Drupal 10.3

This is likely a duplicate of 🐛 logic exception in Drupal\Core\Config\Schema\Mapp Postponed: needs info . Can you verify?

thank you for your fast response.
this is a very critical issue, which makes 10.3 not applicable.

the issue that you mention seems to be the same, but there is no solution there.
In my case, I could see an error even in my javascript console on the browser.

though I don't have a multi-site, eventually taking it back to 10.2.7 fixed the issue.

you need to understand why the 10.3 expect an array to open the data for CKEditor, it might be a very simple issue of method argument definition.