diff --git a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/keys/key_path.rs b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/keys/key_path.rs
index 7242fee87d..51bbfacce1 100644
--- a/moli-renderer-v8/src/context_bootstrap/indexed_db/core/keys/key_path.rs
+++ b/moli-renderer-v8/src/context_bootstrap/indexed_db/core/keys/key_path.rs
@@ -7,9 +7,12 @@ pub(in crate::context_bootstrap::indexed_db) fn parse_idb_key_path<'s>(
     value: v8::Local<'s, v8::Value>,
     context: webidl::Context,
 ) -> Result<KeyPath, webidl::WebIdlError> {
-    if should_parse_key_path_sequence(scope, value, context)? {
-        let key_path =
-            webidl::convert::<webidl::Sequence<webidl::DomString>>(scope, value, context)?;
+    if let Some(key_path) = webidl::convert_optional_sequence::<webidl::DomString>(
+        scope,
+        value,
+        context,
+        &Default::default(),
+    )? {
         return Ok(KeyPath::Sequence(
             key_path.0.into_iter().map(Into::into).collect(),
         ));
@@ -60,22 +63,3 @@ pub(in crate::context_bootstrap::indexed_db) fn key_path_from_js_value<'s>(
         .to_string(scope)
         .map(|value| KeyPath::String(value.to_rust_string_lossy(scope)))
 }
-
-fn should_parse_key_path_sequence<'s>(
-    scope: &mut v8::PinScope<'s, '_>,
-    value: v8::Local<'s, v8::Value>,
-    context: webidl::Context,
-) -> Result<bool, webidl::WebIdlError> {
-    if value.is_string() {
-        return Ok(false);
-    }
-    let Ok(object) = v8::Local::<v8::Object>::try_from(value) else {
-        return Ok(false);
-    };
-    let iterator_key = v8::Symbol::get_iterator(scope);
-    let Some(iterator) = webidl::symbol_property_result(scope, object, iterator_key, context)?
-    else {
-        return Ok(false);
-    };
-    Ok(!iterator.is_null_or_undefined())
-}
diff --git a/moli-renderer-v8/src/script_vm/tests/indexed_db.rs b/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
index b91e0fff39..b7d0478876 100644
--- a/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
+++ b/moli-renderer-v8/src/script_vm/tests/indexed_db.rs
@@ -5773,3 +5773,40 @@ fn indexed_db_put_rejects_non_serializable_platform_objects() {
 
     assert_eq!(result, "DataCloneError|DataCloneError|DataCloneError");
 }
+
+#[test]
+fn indexed_db_key_path_reads_iterator_once() {
+    let mut vm = new_storage_page_task_executor_test_vm("https://key-path-iterator.test/");
+    vm.eval(
+        r#"
+      globalThis.keyPathResult = 'pending';
+      const open = indexedDB.open('key-path-iterator', 1);
+      open.onupgradeneeded = () => {
+        try {
+          let reads = 0;
+          const keyPath = {
+            get [Symbol.iterator]() {
+              if (++reads > 1) throw new Error('iterator read twice');
+              return function* () { yield 'id'; };
+            }
+          };
+          const store = open.result.createObjectStore('values', {keyPath});
+          if (reads !== 1 || String(store.keyPath) !== 'id') throw new Error('store key path');
+          reads = 0;
+          const index = store.createIndex('by-id', keyPath);
+          if (reads !== 1 || String(index.keyPath) !== 'id') throw new Error('index key path');
+          const sentinel = {};
+          const throwing = {get [Symbol.iterator]() { throw sentinel; }};
+          try { store.createIndex('throws', throwing); throw new Error('missing exception'); }
+          catch (error) { if (error !== sentinel) throw error; }
+          globalThis.keyPathResult = 'pass';
+        } catch (error) { globalThis.keyPathResult = String(error); }
+      };
+    "#,
+    )
+    .unwrap();
+    assert_eq!(
+        vm.eval_after_selected_page_tasks("keyPathResult").unwrap(),
+        "pass"
+    );
+}