Hello all,
apparently the check of the version of the editor is a new configuration option, described here Class Config (CKEDITOR.config) | CKEditor 4 API docs .
It was added in CKEditor version 4.22.0; XWiki upgraded to CKEditor 4.22.1 in this ticket Loading... .
From what I tested and from what I understand from the ckeditor configuration, the check itself can be disabled by adding:
config.versionCheck = false;
in the CKEditor configuration in XWiki in the administration in the advanced section of the editor configuration: https://extensions.xwiki.org/xwiki/bin/view/Extension/CKEditor%20Integration/#HAdministrationSection .
This will disable the warning because it will prevent the editor from checking its own version, but it will not fix the version of the editor in any way.
Hope this helps,
Anca