diff --git a/lib/types/account-types.js b/lib/types/account-types.js
--- a/lib/types/account-types.js
+++ b/lib/types/account-types.js
@@ -72,7 +72,7 @@
   rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
   currentUserInfo: LoggedInUserInfo,
   cookieChange: {
-    threadInfos: RawThreadInfos,
+    threadInfos: MinimallyEncodedRawThreadInfos,
     userInfos: $ReadOnlyArray<UserInfo>,
   },
 };
@@ -80,7 +80,7 @@
 export type RegisterResult = {
   +currentUserInfo: LoggedInUserInfo,
   +rawMessageInfos: $ReadOnlyArray<RawMessageInfo>,
-  +threadInfos: RawThreadInfos,
+  +threadInfos: MinimallyEncodedRawThreadInfos,
   +userInfos: $ReadOnlyArray<UserInfo>,
   +calendarQuery: CalendarQuery,
 };