I also get this message:
Joomla\CMS\Filesystem\Folder::files: Path is not a folder. Path: ....../public_html/plugins/system/jcemediabox/addons
Layout "manager_popup" not found in Paths ...../public_html/components/com_jce/editor/libraries/views/plugin/tmpl
What can I do to solve this?
I use:
Joomla 4.0.5
PHP 8.1.0
JCE Editor 2.9.18