diff --git a/testing/web-platform/tests/native-file-system/resources/messaging-serialize-helpers.js b/testing/web-platform/tests/native-file-system/resources/messaging-serialize-helpers.js
index 0d6980090d0a2..5cc7e125f29dc 100644
--- a/testing/web-platform/tests/native-file-system/resources/messaging-serialize-helpers.js
+++ b/testing/web-platform/tests/native-file-system/resources/messaging-serialize-helpers.js
@@ -31,10 +31,10 @@ async function serialize_handle(handle) {
 
 async function serialize_file_system_handle(handle) {
   const read_permission =
-    await handle.queryPermission({ writable: false });
+    await handle.queryPermission({ mode: 'read' });
 
   const write_permission =
-    await handle.queryPermission({ writable: true })
+    await handle.queryPermission({ mode: 'readwrite' })
 
   return {
     kind: handle.kind,
diff --git a/testing/web-platform/tests/native-file-system/resources/native-fs-test-helpers.js b/testing/web-platform/tests/native-file-system/resources/native-fs-test-helpers.js
index 82c587fc3c60d..6ae9700db885f 100644
--- a/testing/web-platform/tests/native-file-system/resources/native-fs-test-helpers.js
+++ b/testing/web-platform/tests/native-file-system/resources/native-fs-test-helpers.js
@@ -41,14 +41,14 @@ function directory_test(func, description) {
 }
 
 directory_test(async (t, dir) => {
-  assert_equals(await dir.queryPermission({writable: false}), 'granted');
+  assert_equals(await dir.queryPermission({mode: 'read'}), 'granted');
 }, 'User succesfully selected an empty directory.');
 
 directory_test(async (t, dir) => {
-  const status = await dir.queryPermission({writable: true});
+  const status = await dir.queryPermission({mode: 'readwrite'});
   if (status == 'granted')
     return;
 
   await window.test_driver.bless('ask for write permission');
-  assert_equals(await dir.requestPermission({writable: true}), 'granted');
+  assert_equals(await dir.requestPermission({mode: 'readwrite'}), 'granted');
 }, 'User granted write access.');
diff --git a/testing/web-platform/tests/native-file-system/showSaveFilePicker-manual.https.html b/testing/web-platform/tests/native-file-system/showSaveFilePicker-manual.https.html
index 022f67771d7f1..451a0fb9c7ff3 100644
--- a/testing/web-platform/tests/native-file-system/showSaveFilePicker-manual.https.html
+++ b/testing/web-platform/tests/native-file-system/showSaveFilePicker-manual.https.html
@@ -26,7 +26,7 @@
 
     promise_test(async t => {
       assert_equals(await file.queryPermission(), 'granted');
-      assert_equals(await file.queryPermission({ writable: true }), 'granted');
+      assert_equals(await file.queryPermission({ mode: 'readwrite' }), 'granted');
     }, 'showSaveFilePicker returns correct permissions');
   }, 'showSaveFilePicker works');