diff --git a/web/chat/chat-thread-composer.react.js b/web/chat/chat-thread-composer.react.js
--- a/web/chat/chat-thread-composer.react.js
+++ b/web/chat/chat-thread-composer.react.js
@@ -23,7 +23,7 @@
 };
 
 function ChatThreadComposer(props: Props): React.Node {
-  const { userInfoInputArray, otherUserInfos, threadID } = props;
+  const { userInfoInputArray, otherUserInfos, threadID, inputState } = props;
 
   const [usernameInputText, setUsernameInputText] = React.useState('');
 
@@ -129,6 +129,14 @@
     return <div className={css.userSelectedTags}>{labels}</div>;
   }, [userInfoInputArray, onRemoveUserFromSelected]);
 
+  React.useEffect(() => {
+    if (!inputState) {
+      return;
+    }
+    inputState.registerSendCallback(hideSearch);
+    return () => inputState.unregisterSendCallback(hideSearch);
+  }, [hideSearch, inputState]);
+
   const threadSearchContainerStyles = React.useMemo(
     () =>
       classNames(css.threadSearchContainer, {