diff --git a/src/Umbraco.Web.UI.Client/src/core/services/modal/layouts/content-picker/modal-layout-content-picker.element.ts b/src/Umbraco.Web.UI.Client/src/core/services/modal/layouts/content-picker/modal-layout-content-picker.element.ts
index c36ea6d1a1..826fd4731e 100644
--- a/src/Umbraco.Web.UI.Client/src/core/services/modal/layouts/content-picker/modal-layout-content-picker.element.ts
+++ b/src/Umbraco.Web.UI.Client/src/core/services/modal/layouts/content-picker/modal-layout-content-picker.element.ts
@@ -4,7 +4,7 @@ import { customElement, state } from 'lit/decorators.js';
 import { UmbModalLayoutElement } from '../modal-layout.element';
 
 export interface UmbModalContentPickerData {
-	multiple: boolean;
+	multiple?: boolean;
 }
 
 @customElement('umb-modal-layout-content-picker')