diff --git a/static/messages.js b/static/messages.js
index 261582ec..e24f90d1 100644
--- a/static/messages.js
+++ b/static/messages.js
@@ -2613,7 +2613,7 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
         if(streamId){
           const st=await api(`/api/chat/stream/status?stream_id=${encodeURIComponent(streamId)}`);
           if(st.active){
-            setComposerStatus('Reconnected');
+            setComposerStatus('Reconnected',1000);
             _wireSSE(new EventSource(new URL(`api/chat/stream?stream_id=${encodeURIComponent(streamId)}${_runJournalReplayParams()}`,document.baseURI||location.href).href,{withCredentials:true}));
             return;
           }
@@ -6648,9 +6648,7 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
           return;
         }
         // Show as a small inline notice, not a full error
-        setComposerStatus(`${d.message||'Warning'}`);
-        // If it's a fallback notice, show it briefly then clear
-        if(d.type==='fallback') setTimeout(()=>setComposerStatus(''),4000);
+        setComposerStatus(`${d.message||'Warning'}`,d.type==='fallback'?4000:undefined);
       }catch(_){}
     });
 
@@ -6699,7 +6697,7 @@ function attachLiveStream(activeSid, streamId, uploaded=[], options={}){
           try{
             const st=await api(`/api/chat/stream/status?stream_id=${encodeURIComponent(streamId)}`);
             if(st&&st.active){
-              setComposerStatus('Reconnected');
+              setComposerStatus('Reconnected',1000);
               _wireSSE(new EventSource(new URL(`api/chat/stream?stream_id=${encodeURIComponent(streamId)}${_runJournalReplayParams()}`,document.baseURI||location.href).href,{withCredentials:true}));
               return;
             }
diff --git a/static/ui.js b/static/ui.js
index c1b8b57e..f98cb2df 100644
--- a/static/ui.js
+++ b/static/ui.js
@@ -7960,7 +7960,13 @@ function setStatus(t){
   showToast(t, 4000);
 }
 
-function setComposerStatus(t){
+let _composerStatusTimer=null;
+
+function setComposerStatus(t,timeoutMs){
+  if(_composerStatusTimer!==null){
+    clearTimeout(_composerStatusTimer);
+    _composerStatusTimer=null;
+  }
   const el=$('composerStatus');
   if(!el)return;
   const statusHidden=!!(window._composerControlVisibility&&window._composerControlVisibility.hide_composer_status);
@@ -7979,6 +7985,14 @@ function setComposerStatus(t){
   el.removeAttribute('aria-hidden');
   el.textContent=t;
   el.style.display='';
+  if(timeoutMs>0){
+    const timer=setTimeout(()=>{
+      if(_composerStatusTimer!==timer)return;
+      _composerStatusTimer=null;
+      setComposerStatus('');
+    },timeoutMs);
+    _composerStatusTimer=timer;
+  }
 }
 
 let _composerLockState=null;
diff --git a/tests/test_composer_status_timeout.py b/tests/test_composer_status_timeout.py
new file mode 100644
index 00000000..961f80a9
--- /dev/null
+++ b/tests/test_composer_status_timeout.py
@@ -0,0 +1,147 @@
+import json
+import re
+import subprocess
+import textwrap
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+UI_JS = (ROOT / "static" / "ui.js").read_text(encoding="utf-8")
+MESSAGES_JS = (ROOT / "static" / "messages.js").read_text(encoding="utf-8")
+
+
+def _function_source(source: str, name: str) -> str:
+    start = source.index(f"function {name}(")
+    brace = source.index("{", start)
+    depth = 0
+    for index in range(brace, len(source)):
+        if source[index] == "{":
+            depth += 1
+        elif source[index] == "}":
+            depth -= 1
+            if depth == 0:
+                return source[start : index + 1]
+    raise AssertionError(f"could not extract {name}")
+
+
+def _composer_status_source(source: str) -> str:
+    owner = "let _composerStatusTimer=null;"
+    owner_start = source.index(owner)
+    function_start = source.index("function setComposerStatus(", owner_start)
+    function_source = _function_source(source, "setComposerStatus")
+    assert owner_start < function_start
+    return source[owner_start : function_start + len(function_source)]
+
+
+def test_composer_status_timeout_is_race_safe():
+    composer_status_source = _composer_status_source(UI_JS)
+    script = textwrap.dedent(
+        f"""
+        const statusElement = {{
+          style: {{display: 'none'}},
+          textContent: '',
+          classList: {{remove() {{}}}},
+          removeAttribute() {{}},
+        }};
+        globalThis.window = {{_composerControlVisibility: {{}}}};
+        globalThis.$ = (id) => id === 'composerStatus' ? statusElement : null;
+
+        let now = 0;
+        let nextTimerId = 1;
+        const timers = new Map();
+        globalThis.setTimeout = (fn, delay) => {{
+          const id = nextTimerId++;
+          timers.set(id, {{fn, due: now + delay}});
+          return id;
+        }};
+        globalThis.clearTimeout = (id) => timers.delete(id);
+        function advance(ms) {{
+          const target = now + ms;
+          while (true) {{
+            let next = null;
+            for (const [id, timer] of timers) {{
+              if (timer.due <= target && (!next || timer.due < next.timer.due)) {{
+                next = {{id, timer}};
+              }}
+            }}
+            if (!next) break;
+            timers.delete(next.id);
+            now = next.timer.due;
+            next.timer.fn();
+          }}
+          now = target;
+        }}
+        function visible() {{
+          return statusElement.style.display !== 'none' && statusElement.textContent;
+        }}
+        function expect(condition, message) {{
+          if (!condition) throw new Error(message);
+        }}
+
+        {composer_status_source}
+
+        setComposerStatus('Reconnected', 1000);
+        expect(visible() === 'Reconnected', 'timed status should be visible immediately');
+        advance(999);
+        expect(visible() === 'Reconnected', 'timed status should remain visible before expiry');
+        advance(1);
+        expect(!visible(), 'timed status should hide at expiry');
+
+        setComposerStatus('Old status', 1000);
+        advance(500);
+        setComposerStatus('New status');
+        advance(500);
+        expect(visible() === 'New status', 'old timer must not clear a newer untimed status');
+
+        setComposerStatus('Same status', 1000);
+        advance(500);
+        setComposerStatus('Same status', 1000);
+        advance(500);
+        expect(visible() === 'Same status', 'repeated timed status needs a fresh timeout');
+        advance(500);
+        expect(!visible(), 'repeated timed status should hide after its fresh timeout');
+
+        setComposerStatus('Untimed status');
+        advance(5000);
+        expect(visible() === 'Untimed status', 'untimed status must remain visible');
+
+        setComposerStatus('Clear me', 1000);
+        setComposerStatus('');
+        expect(!visible(), 'explicit clear must hide immediately');
+        advance(1000);
+        expect(!visible(), 'explicit clear must cancel the owned timer');
+
+        setComposerStatus('Hide me', 1000);
+        window._composerControlVisibility.hide_composer_status = true;
+        setComposerStatus('Still hidden');
+        expect(!visible(), 'hidden-status preference must hide the status');
+        advance(1000);
+        expect(!visible(), 'hidden-status preference must cancel timed expiry');
+        window._composerControlVisibility.hide_composer_status = false;
+
+        process.stdout.write(JSON.stringify({{ok: true}}));
+        """
+    )
+    completed = subprocess.run(
+        ["node", "-e", script],
+        check=True,
+        capture_output=True,
+        text=True,
+    )
+    assert json.loads(completed.stdout) == {"ok": True}
+
+
+def test_messages_wires_all_timed_composer_statuses_through_shared_owner():
+    reconnected_calls = re.findall(
+        r"setComposerStatus\('Reconnected'(?:,[^)]*)?\);", MESSAGES_JS
+    )
+    assert reconnected_calls == [
+        "setComposerStatus('Reconnected',1000);",
+        "setComposerStatus('Reconnected',1000);",
+    ]
+    assert "setComposerStatus('Reconnected');" not in MESSAGES_JS
+    assert (
+        "setComposerStatus(`${d.message||'Warning'}`,d.type==='fallback'?4000:undefined);"
+        in MESSAGES_JS
+    )
+    assert "setTimeout(()=>setComposerStatus(''),4000)" not in MESSAGES_JS
diff --git a/tests/test_issue5139_gateway_approval_offline_notice.py b/tests/test_issue5139_gateway_approval_offline_notice.py
index 94a2cf89..1c6ca173 100644
--- a/tests/test_issue5139_gateway_approval_offline_notice.py
+++ b/tests/test_issue5139_gateway_approval_offline_notice.py
@@ -246,7 +246,7 @@ def test_messages_js_handles_offline_warning_without_touching_unsupported_branch
     assert "Gateway offline" in MESSAGES_JS
     assert "d.type==='approval_gateway_unsupported'" in MESSAGES_JS
     assert "Approvals not supported" in MESSAGES_JS
-    assert "setComposerStatus(`${d.message||'Warning'}`);" in MESSAGES_JS
+    assert "setComposerStatus(`${d.message||'Warning'}`,d.type==='fallback'?4000:undefined);" in MESSAGES_JS
 
 
 def test_gateway_chat_source_mentions_offline_warning_type():