diff --git a/interfaces/savedata.idl b/interfaces/savedata.idl
new file mode 100644
index 00000000000000..4d9e3b98d3c993
--- /dev/null
+++ b/interfaces/savedata.idl
@@ -0,0 +1,10 @@
+// GENERATED CONTENT - DO NOT EDIT
+// Content was automatically extracted by Reffy into reffy-reports
+// (https://github.com/tidoust/reffy-reports)
+// Source: Save Data API (https://wicg.github.io/savedata/)
+
+interface mixin NetworkInformationSaveData {
+  [SameObject] readonly attribute boolean saveData;
+};
+
+NetworkInformation includes NetworkInformationSaveData;
diff --git a/savedata/idlharness.any.js b/savedata/idlharness.any.js
new file mode 100644
index 00000000000000..aad362346ca5fa
--- /dev/null
+++ b/savedata/idlharness.any.js
@@ -0,0 +1,16 @@
+// META: script=/resources/WebIDLParser.js
+// META: script=/resources/idlharness.js
+
+'use strict';
+
+// https://wicg.github.io/savedata/
+
+idl_test(
+  ['savedata'],
+  ['netinfo', 'html', 'dom'],
+  idl_array => {
+    idl_array.add_objects({
+      NetworkInformation: ['navigator.connection']
+    });
+  }
+);