Clear stale chat stream indicators

static/js/chat.js

@@ -4141,7 +4141,10 @@ import { wireArrowUpRecall, getLastUserMessageFromChatHistory } from './composer
     if (!sessionId) return;
     try {
       const res = await fetch(`${API_BASE}/api/research/status/${sessionId}`);
-      if (!res.ok) return; // 404 = no research for this session
+      if (!res.ok) {
+        if (sessionModule && sessionModule.clearResearching) sessionModule.clearResearching(sessionId);
+        return; // 404 = no research for this session
+      }
       const data = await res.json();
 
       if (data.status === 'done') {

static/js/sessions.js

@@ -2433,6 +2433,17 @@ export function clearStreaming(sessionId) {
   _updateRailNotifs();
 }
 
+function _clearRunningState(sessionId) {
+  if (!sessionId) return;
+  var changed = false;
+  if (_researchingSessions.delete(sessionId)) changed = true;
+  if (_streamingSessions.delete(sessionId)) changed = true;
+  if (changed) {
+    _updateResearchDots();
+    _updateRailNotifs();
+  }
+}
+
 export function markStreamComplete(sessionId) {
   _researchingSessions.delete(sessionId);
   _streamingSessions.delete(sessionId);
@@ -2503,9 +2514,15 @@ async function _checkServerStream(sessionId) {
     if (window.chatModule && window.chatModule.hasActiveStream && window.chatModule.hasActiveStream(sessionId)) return;
 
     const res = await fetch(`${API_BASE}/api/chat/stream_status/${sessionId}`);
-    if (!res.ok) return; // 404 = no active stream
+    if (!res.ok) {
+      _clearRunningState(sessionId);
+      return; // 404 = no active stream
+    }
     const info = await res.json();
-    if (info.status !== 'streaming') return;
+    if (info.status !== 'streaming') {
+      _clearRunningState(sessionId);
+      return;
+    }
 
     // Skip if this is a research stream — research has its own progress UI
     if (info.mode === 'research' || info.is_research) return;