chromium/third_party/blink/renderer/modules/shared_storage/window_shared_storage.idl

[
  RuntimeEnabled=SharedStorageAPI,
  ImplementedAs=WindowSharedStorage
] partial interface Window {
  [
    MeasureAs=SharedStorageAPI_SharedStorage_DOMReference,
    SecureContext,
    RaisesException
  ] readonly attribute SharedStorage sharedStorage;
};