diff --git a/ghost/portal/src/data-attributes.js b/ghost/portal/src/data-attributes.js
index f6cc7d2736..1f141fb5d6 100644
--- a/ghost/portal/src/data-attributes.js
+++ b/ghost/portal/src/data-attributes.js
@@ -15,7 +15,7 @@ function handleDataAttributes({siteUrl, site, member}) {
             form.classList.remove('success', 'invalid', 'error');
             let emailInput = event.target.querySelector('input[data-members-email]');
             let nameInput = event.target.querySelector('input[data-members-name]');
-            let email = emailInput.value;
+            let email = emailInput?.value;
             let name = (nameInput && nameInput.value) || undefined;
             let emailType = undefined;
             let labels = [];