In a craft environment with multiple sites with different languages copy the content of a CKeditor field (with nested entries) from an entry on a secondary site.
Make a new entry on the same site and attempt to paste the content. You should see invalid entry ID errors for each of the nested entries.
Description
Issue is related to: https://github.com/craftcms/ckeditor/issues/254 The problem is resolved for the default site but still exists on additional sites.
Steps to reproduce
Additional info