Text/HTML Widget 1 Configure Error

Problem/Motivation

/admin/content-planner/dashboard/configure/custom_html_block_2?destination=%2Fadmin%2Fcontent-planner%2Fdashboard%2Fsettings

Drupal\Component\Plugin\Exception\PluginNotFoundException: The "fakeobjects" plugin does not exist. Valid plugin IDs for Drupal\ckeditor\CKEditorPluginManager are: link, stylescombo, drupalmedialibrary, drupalimage, drupalimagecaption, internal, drupallink, drupalmedia, language in Drupal\Core\Plugin\DefaultPluginManager->doGetDefinition() (line 53 of /core/lib/Drupal/Component/Plugin/Discovery/DiscoveryTrait.php).

Steps to reproduce

/admin/content-planner/dashboard/settings

Check the box next to "Text/HTML Widget 1" and click "Configure"