diff --git a/lib/selectors/user-selectors.js b/lib/selectors/user-selectors.js
--- a/lib/selectors/user-selectors.js
+++ b/lib/selectors/user-selectors.js
@@ -163,23 +163,6 @@
   },
 );
 
-function searchIndexFromUserInfos(userInfos: {
-  [id: string]: AccountUserInfo,
-}) {
-  const searchIndex = new SearchIndex();
-  for (const id in userInfos) {
-    searchIndex.addEntry(id, userInfos[id].username);
-  }
-  return searchIndex;
-}
-
-const userSearchIndexForPotentialMembers: (
-  state: BaseAppState<>,
-) => SearchIndex = createSelector(
-  userInfoSelectorForPotentialMembers,
-  searchIndexFromUserInfos,
-);
-
 const isLoggedIn = (state: BaseAppState<>): boolean =>
   !!(
     state.currentUserInfo &&
@@ -200,16 +183,6 @@
   }
 };
 
-const userStoreSearchIndex: (state: BaseAppState<>) => SearchIndex =
-  createSelector(
-    (state: BaseAppState<>) => state.userStore.userInfos,
-    (userInfos: UserInfos) => {
-      const searchIndex = new SearchIndex();
-      addUsersToSearchIndex(userInfos, searchIndex);
-      return searchIndex;
-    },
-  );
-
 const userStoreMentionSearchIndex: (
   state: BaseAppState<>,
 ) => SentencePrefixSearchIndex = createSelector(
@@ -266,9 +239,7 @@
   getRelativeMemberInfos,
   relativeMemberInfoSelectorForMembersOfThread,
   userInfoSelectorForPotentialMembers,
-  userSearchIndexForPotentialMembers,
   isLoggedIn,
-  userStoreSearchIndex,
   userStoreMentionSearchIndex,
   usersWithPersonalThreadSelector,
   savedEmojiAvatarSelectorForCurrentUser,