Hi,
The toolbar group name of the color button is “colors”, not “colorbutton”. Which button has which name and which toolbar group is documented at https://documentation.bloomreach.com/library/concepts/document-types/html-fields/ckeditor-toolbar-items.html CKEditor itself does not document this at all AFAIK, you basically have to rely on the source code or our documentation page.
So the color button should appear with the following configuration:
ckeditor.config.appended.json: { toolbarGroups: [ { name: ‘colors’ } ] }
ckeditor.config.overlayed.json: { extraPlugins: ‘colorbutton’ }
hope that helps,
Mathijs