diff --git a/src/lib/types.ts b/src/lib/types.ts
index 90338e1d..3ed6913b 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -421,11 +421,11 @@ export interface JSONEditorPropsOptional {
   statusBar?: boolean
   escapeControlCharacters?: boolean
   escapeUnicodeCharacters?: boolean
-  flattenColumns: true
-  parser: JSONParser
-  validator: Validator | null
-  validationParser: JSONParser
-  pathParser: JSONPathParser
+  flattenColumns?: true
+  parser?: JSONParser
+  validator?: Validator | null
+  validationParser?: JSONParser
+  pathParser?: JSONPathParser
 
   queryLanguages?: QueryLanguage[]
   queryLanguageId?: string