From 80d66538c25c81fd6dfbcf61ce6d994cacf27e46 Mon Sep 17 00:00:00 2001
From: Andre Padez <andre.padez@gmail.com>
Date: Mon, 10 Aug 2026 21:51:04 +0100
Subject: [PATCH] fix the render loop I was warned about in the file I edited
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React #185, maximum update depth, and the page with it.

usePublishChatTabName named useGlobal setter as an effect dependency. useGlobal rebuilds that
setter every render, so the effect re-ran every render, set global state, and rendered again.
The publisher directly above it in the same file documents this exact hazard — I copied the
shape and not the reason.

Now through a ref, depending on the string alone, identical to usePublishPageTitle.

Also stabilised setPaneTarget with useCallback. It is handed to every pane as onChange and a
pane puts it in a context others read, so a fresh identity each render is the same loop
waiting for the first consumer that depends on it. The active tab key is read through a ref
so it never has to be a dependency.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 .../src/apps/ChatHistory/ChatTabs.tsx         | 25 +++++++++++++------
 src/workspaces/officerdev/src/page-title.ts   | 16 +++++++-----
 2 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/src/workspaces/officerdev/src/apps/ChatHistory/ChatTabs.tsx b/src/workspaces/officerdev/src/apps/ChatHistory/ChatTabs.tsx
index 896c2d28..2dbefff3 100644
--- a/src/workspaces/officerdev/src/apps/ChatHistory/ChatTabs.tsx
+++ b/src/workspaces/officerdev/src/apps/ChatHistory/ChatTabs.tsx
@@ -1,4 +1,4 @@
-import { useEffect, useRef, useState } from 'react';
+import { useCallback, useEffect, useRef, useState } from 'react';
 import { Columns2, Plus, X } from 'lucide-react';
 import { connectionLabel } from 'hooks/connections';
 import { usePublishChatTabName } from '../../page-title';
@@ -63,6 +63,9 @@ export const ChatTabs = () => {
   const [renamingKey, setRenamingKey] = useState<string | null>(null);
   const [renameValue, setRenameValue] = useState('');
   const restored = useRef(false);
+  // Read inside the stable callback above, so it never has to be a dependency.
+  const activeKeyRef = useRef(activeKey);
+  activeKeyRef.current = activeKey;
 
   // First render picks the first tab; afterwards the user owns it.
   useEffect(() => {
@@ -132,12 +135,20 @@ export const ChatTabs = () => {
       tab.panes.length <= 1 ? tab : { ...tab, panes: tab.panes.filter((pane) => pane.key !== paneKey) },
     );
 
-  const setPaneTarget = (paneKey: string, target: SelectedSession | null) =>
-    active &&
-    update(active.key, (tab) => ({
-      ...tab,
-      panes: tab.panes.map((pane) => (pane.key === paneKey ? { ...pane, target } : pane)),
-    }));
+  // Stable across renders on purpose. It is handed to every pane as `onChange`, and a pane passes it
+  // into a context that other components read — an identity that changed every render would make any
+  // effect depending on it re-run forever, which is the render loop this file already caused once.
+  const setPaneTarget = useCallback(
+    (paneKey: string, target: SelectedSession | null) =>
+      setTabs((prev) =>
+        prev.map((tab) =>
+          tab.key !== activeKeyRef.current
+            ? tab
+            : { ...tab, panes: tab.panes.map((pane) => (pane.key === paneKey ? { ...pane, target } : pane)) },
+        ),
+      ),
+    [],
+  );
 
   if (!active) return null;
 
diff --git a/src/workspaces/officerdev/src/page-title.ts b/src/workspaces/officerdev/src/page-title.ts
index 8f46a446..fa148fb2 100644
--- a/src/workspaces/officerdev/src/page-title.ts
+++ b/src/workspaces/officerdev/src/page-title.ts
@@ -76,12 +76,16 @@ export const useChatTabName = () => useGlobal<string | null>(CHAT_TAB_NAME, null
  */
 export function usePublishChatTabName(name: string | null) {
   const [, setName] = useGlobal<string | null>(CHAT_TAB_NAME, null);
-  const nameRef = useRef(name);
-  nameRef.current = name;
+
+  // Through a ref, and depending on the STRING only — exactly as `usePublishPageTitle` does, for the
+  // reason documented there: `useGlobal` rebuilds its setter every render, so naming it as a dependency
+  // re-runs this effect on every render, which sets global state, which renders again. That is React
+  // error #185, and it took the whole page down until the deps were narrowed to the value itself.
+  const setNameRef = useRef(setName);
+  setNameRef.current = setName;
 
   useEffect(() => {
-    setName(nameRef.current);
-  }, [name, setName]);
-
-  useEffect(() => () => setName(null), [setName]);
+    setNameRef.current(name);
+    return () => setNameRef.current(null);
+  }, [name]);
 }