diff --git a/lib/shared/avatar-utils.js b/lib/shared/avatar-utils.js
--- a/lib/shared/avatar-utils.js
+++ b/lib/shared/avatar-utils.js
@@ -6,6 +6,7 @@
 
 import { getETHAddressForUserInfo } from './account-utils.js';
 import { selectedThreadColors } from './color-utils.js';
+import { extractFIDFromUserID } from './id-utils.js';
 import { threadOtherMembers } from './thread-utils.js';
 import {
   threadTypeIsPersonal,
@@ -423,6 +424,33 @@
   };
 }
 
+function useDisplayUserForThread(
+  displayUserIDForThread: ?string,
+  userInfos: UserInfos,
+  auxUserInfos: { +[userID: string]: { +fid?: ?string, ... }, ... },
+): ?UsernameAndFID {
+  return React.useMemo(() => {
+    if (!displayUserIDForThread) {
+      return null;
+    }
+
+    const fid = extractFIDFromUserID(displayUserIDForThread);
+    if (fid) {
+      return {
+        farcasterID: fid,
+      };
+    }
+
+    const userBase = userInfos[displayUserIDForThread];
+    const farcasterID = auxUserInfos[displayUserIDForThread]?.fid;
+
+    return {
+      ...userBase,
+      farcasterID,
+    };
+  }, [displayUserIDForThread, userInfos, auxUserInfos]);
+}
+
 export {
   defaultAnonymousUserEmojiAvatar,
   defaultEmojiAvatars,
@@ -433,4 +461,5 @@
   getAvatarForThread,
   useResolvedUserAvatar,
   useResolvedThreadAvatar,
+  useDisplayUserForThread,
 };
diff --git a/native/avatars/thread-avatar.react.js b/native/avatars/thread-avatar.react.js
--- a/native/avatars/thread-avatar.react.js
+++ b/native/avatars/thread-avatar.react.js
@@ -3,7 +3,10 @@
 import * as React from 'react';
 
 import { useAvatarForThread } from 'lib/hooks/avatar-hooks.js';
-import { useResolvedThreadAvatar } from 'lib/shared/avatar-utils.js';
+import {
+  useResolvedThreadAvatar,
+  useDisplayUserForThread,
+} from 'lib/shared/avatar-utils.js';
 import { getSingleOtherUser, getCommunity } from 'lib/shared/thread-utils.js';
 import {
   threadTypeIsPersonal,
@@ -50,20 +53,14 @@
     displayUserIDForThread = getSingleOtherUser(threadInfo, viewerID);
   }
 
-  const displayUser = useSelector(state => {
-    if (!displayUserIDForThread) {
-      return null;
-    }
-
-    const userBase = state.userStore.userInfos[displayUserIDForThread];
-    const farcasterID =
-      state.auxUserStore.auxUserInfos[displayUserIDForThread]?.fid;
+  const userInfos = useSelector(state => state.userStore.userInfos);
+  const auxUserInfos = useSelector(state => state.auxUserStore.auxUserInfos);
 
-    return {
-      ...userBase,
-      farcasterID,
-    };
-  });
+  const displayUser = useDisplayUserForThread(
+    displayUserIDForThread,
+    userInfos,
+    auxUserInfos,
+  );
 
   const resolvedThreadAvatar = useResolvedThreadAvatar(avatarInfo, {
     userProfileInfo: displayUser,
diff --git a/web/avatars/thread-avatar.react.js b/web/avatars/thread-avatar.react.js
--- a/web/avatars/thread-avatar.react.js
+++ b/web/avatars/thread-avatar.react.js
@@ -3,7 +3,10 @@
 import * as React from 'react';
 
 import { useAvatarForThread } from 'lib/hooks/avatar-hooks.js';
-import { useResolvedThreadAvatar } from 'lib/shared/avatar-utils.js';
+import {
+  useResolvedThreadAvatar,
+  useDisplayUserForThread,
+} from 'lib/shared/avatar-utils.js';
 import { getSingleOtherUser, getCommunity } from 'lib/shared/thread-utils.js';
 import {
   threadTypeIsPersonal,
@@ -49,20 +52,14 @@
     displayUserIDForThread = getSingleOtherUser(threadInfo, viewerID);
   }
 
-  const displayUser = useSelector(state => {
-    if (!displayUserIDForThread) {
-      return null;
-    }
-
-    const userBase = state.userStore.userInfos[displayUserIDForThread];
-    const farcasterID =
-      state.auxUserStore.auxUserInfos[displayUserIDForThread]?.fid;
+  const userInfos = useSelector(state => state.userStore.userInfos);
+  const auxUserInfos = useSelector(state => state.auxUserStore.auxUserInfos);
 
-    return {
-      ...userBase,
-      farcasterID,
-    };
-  });
+  const displayUser = useDisplayUserForThread(
+    displayUserIDForThread,
+    userInfos,
+    auxUserInfos,
+  );
 
   const resolvedThreadAvatar = useResolvedThreadAvatar(avatarInfo, {
     userProfileInfo: displayUser,