Issue #3427200 by gedvan, Wim Leers: CKEditor 5: Javascript error when plugin settings has NULL value

(cherry picked from commit 695c6a53ca)

core/modules/ckeditor5/js/ckeditor5.js

@@ -116,6 +116,10 @@
       });
     }
 
+    if (config === null) {
+      return null;
+    }
+
     return Object.entries(config).reduce((processed, [key, value]) => {
       if (typeof value === 'object') {
         // Check for null values.