diff --git a/packages/builder/src/components/design/AppPreview/CurrentItemPreview.svelte b/packages/builder/src/components/design/AppPreview/CurrentItemPreview.svelte
index 8bf8570d31..28bc50d15a 100644
--- a/packages/builder/src/components/design/AppPreview/CurrentItemPreview.svelte
+++ b/packages/builder/src/components/design/AppPreview/CurrentItemPreview.svelte
@@ -68,6 +68,7 @@
     customTheme: $store.customTheme,
     previewDevice: $store.previewDevice,
     messagePassing: $store.clientFeatures.messagePassing,
+    isBudibaseEvent: true
   }
   $: json = JSON.stringify(previewData)
 
diff --git a/packages/builder/src/components/design/AppPreview/iframeTemplate.js b/packages/builder/src/components/design/AppPreview/iframeTemplate.js
index 15321c5eff..c265a64d53 100644
--- a/packages/builder/src/components/design/AppPreview/iframeTemplate.js
+++ b/packages/builder/src/components/design/AppPreview/iframeTemplate.js
@@ -52,7 +52,7 @@ export default `
           console.error("Client received invalid JSON")
           // Ignore
         }
-        if (!parsed) {
+        if (!parsed || !parsed.isBudibaseEvent) {
           return
         }