diff --git a/tests/regression/interactive-toast-and-terminal-handoff-regression.test.mjs b/tests/regression/interactive-toast-and-terminal-handoff-regression.test.mjs
new file mode 100644
index 0000000..466bd32
--- /dev/null
+++ b/tests/regression/interactive-toast-and-terminal-handoff-regression.test.mjs
@@ -0,0 +1,59 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+const repoRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "../..");
+const read = (relativePath) =>
+  fs.readFileSync(path.join(repoRoot, relativePath), "utf8");
+
+test("toast overlay scopes notifications to the active session and exposes dismissal", () => {
+  const source = read("webview/shared/src/chat/ToastOverlay.tsx");
+
+  assert.match(
+    source,
+    /notification\.sessionId\s*&&\s*sessionId[\s\S]*notification\.sessionId\s*!==\s*sessionId/,
+    "toast rendering must reject notifications belonging to another session",
+  );
+  assert.match(
+    source,
+    /aria-label=\"Dismiss notification\"[\s\S]*onClick=\{dismissActiveToast\}/,
+    "toast rendering must provide an explicit dismiss action",
+  );
+  assert.match(
+    source,
+    /const dismissActiveToast = \(\) => \{[\s\S]*clearActiveTimer\(\)[\s\S]*showNextToast\(\)/,
+    "dismissing a toast must release its timer and advance the queue",
+  );
+});
+
+test("interactive composer ignores events from another session", () => {
+  const source = read("webview/shared/src/chat/PanelComponents.tsx");
+
+  const sessionFilterCount = (source.match(/event\.sessionID === currentSessionId/g) ?? []).length;
+  assert.ok(
+    sessionFilterCount >= 3,
+    "top-level, streaming, and hydrated interactive events must share session filtering",
+  );
+  assert.match(
+    source,
+    /dismissedInteractiveEventKeys, currentSessionId\]/,
+    "the composer must recompute when the active session changes",
+  );
+});
+
+test("terminal transcript handoff does not use a stale deferred snapshot", () => {
+  const source = read("webview/shared/src/chat/ChatShell.tsx");
+
+  assert.match(
+    source,
+    /const transcriptSnapshotForRender = state\.streaming\?\.isActive\s*\n\s*\? deferredTranscriptSnapshot\s*\n\s*: transcriptSnapshot/,
+    "completed turns must switch to the current transcript snapshot immediately",
+  );
+  assert.match(
+    source,
+    /renderMessages=\{transcriptSnapshotForRender\.renderMessages\}/,
+    "the transcript must consume the same atomic snapshot as its visible entries",
+  );
+});
diff --git a/webview/shared/src/chat/ChatShell.tsx b/webview/shared/src/chat/ChatShell.tsx
index 8064ffb..c20b61c 100644
--- a/webview/shared/src/chat/ChatShell.tsx
+++ b/webview/shared/src/chat/ChatShell.tsx
@@ -3720,8 +3720,16 @@ function ChatContent() {
     [renderMessages, visibleConversationEntries],
   );
   const deferredTranscriptSnapshot = useDeferredValue(transcriptSnapshot);
+  // The deferred snapshot is useful while tokens are arriving, but retaining
+  // it after the stream becomes inactive leaves the live card unmounted before
+  // the completed assistant transcript is painted. Use the current atomic
+  // snapshot for the terminal handoff so the response body and prompt appear
+  // in the same commit.
+  const transcriptSnapshotForRender = state.streaming?.isActive
+    ? deferredTranscriptSnapshot
+    : transcriptSnapshot;
   const deferredVisibleConversationEntries =
-    deferredTranscriptSnapshot.visibleConversationEntries;
+    transcriptSnapshotForRender.visibleConversationEntries;
   const transcriptScrollViewport =
     deferredVisibleConversationEntries.length >= VIRTUALIZED_TRANSCRIPT_MIN_ENTRIES
       ? scrollRenderViewport
@@ -4111,7 +4119,7 @@ function ChatContent() {
             isProcessing={state.isProcessing}
             lastCompactedAt={state.lastCompactedAt}
             onSetBlockExpanded={handleSetBlockExpanded}
-            renderMessages={deferredTranscriptSnapshot.renderMessages}
+            renderMessages={transcriptSnapshotForRender.renderMessages}
             resolveAgentColor={resolveAgentColor}
             selectedAgent={state.selectedAgent}
             streamingAgent={deferredStreamingAgent}
diff --git a/webview/shared/src/chat/PanelComponents.tsx b/webview/shared/src/chat/PanelComponents.tsx
index 6c42d1a..62667c1 100644
--- a/webview/shared/src/chat/PanelComponents.tsx
+++ b/webview/shared/src/chat/PanelComponents.tsx
@@ -2182,18 +2182,33 @@ export const InputWrapper = memo(function InputWrapper() {
 
     // 1. Top-level interactive events (out-of-band questions, etc.)
     if (Array.isArray(interactiveEvents)) {
-      events = [...events, ...interactiveEvents];
+      events = [
+        ...events,
+        ...interactiveEvents.filter(
+          (event) => !event.sessionID || !currentSessionId || event.sessionID === currentSessionId,
+        ),
+      ];
     }
 
     // 2. Interactive events from currently streaming response
     if (streaming?.isActive && Array.isArray(streaming.interactiveEvents)) {
-      events = [...events, ...streaming.interactiveEvents];
+      events = [
+        ...events,
+        ...streaming.interactiveEvents.filter(
+          (event) => !event.sessionID || !currentSessionId || event.sessionID === currentSessionId,
+        ),
+      ];
     } else {
       // 3. If not streaming, fallback to interactive events from the latest assistant message,
       // but ONLY if the assistant is the absolute last speaker in the conversation.
       const lastMsg = messages.length > 0 ? messages[messages.length - 1] : null;
       if (lastMsg?.role === "assistant" && Array.isArray(lastMsg.interactiveEvents)) {
-        events = [...events, ...lastMsg.interactiveEvents];
+        events = [
+          ...events,
+          ...lastMsg.interactiveEvents.filter(
+            (event) => !event.sessionID || !currentSessionId || event.sessionID === currentSessionId,
+          ),
+        ];
       }
     }
 
@@ -2201,7 +2216,7 @@ export const InputWrapper = memo(function InputWrapper() {
       events,
       dismissedInteractiveEventKeys,
     );
-  }, [messages, streaming, interactiveEvents, dismissedInteractiveEventKeys]);
+  }, [messages, streaming, interactiveEvents, dismissedInteractiveEventKeys, currentSessionId]);
 
   const filteredCommands = useMemo(() => {
     if (!slashTrigger) {
diff --git a/webview/shared/src/chat/ToastOverlay.tsx b/webview/shared/src/chat/ToastOverlay.tsx
index fcc8ed6..93aadec 100644
--- a/webview/shared/src/chat/ToastOverlay.tsx
+++ b/webview/shared/src/chat/ToastOverlay.tsx
@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useRef, useState } from "react";
-import { AlertTriangle, CheckCircle2, Info, XCircle } from "lucide-react";
+import { AlertTriangle, CheckCircle2, Info, X, XCircle } from "lucide-react";
 
 import { cn } from "../utils";
 import logger from "./lib/logger";
@@ -60,13 +60,24 @@ export function LiveEventBanner({
   const notifications = useMemo(() => {
     const persisted = extractCentralizedToastNotifications(rawSdkEventPayloads);
     const allNotifications = [...persisted, ...(liveNotifications ?? [])];
-    const placedNotifications = allNotifications.filter((notification) =>
-      placement === "composer"
+    const placedNotifications = allNotifications.filter((notification) => {
+      // A late SSE/debug payload from another session must never become a
+      // visible toast in the active session. Untagged notifications are kept
+      // for compatibility with older SDK payloads and are scoped by the
+      // reducer/live-event route already.
+      if (
+        notification.sessionId &&
+        sessionId &&
+        notification.sessionId !== sessionId
+      ) {
+        return false;
+      }
+      return placement === "composer"
         ? notification.type === "session.status"
-        : notification.type !== "session.status",
-    );
+        : notification.type !== "session.status";
+    });
     return placedNotifications;
-  }, [liveNotifications, placement, rawSdkEventPayloads]);
+  }, [liveNotifications, placement, rawSdkEventPayloads, sessionId]);
   const [activeToast, setActiveToast] = useState<CentralizedToastNotification | null>(null);
   const [toastNow, setToastNow] = useState(() => Date.now());
   const toastQueueRef = useRef<CentralizedToastNotification[]>([]);
@@ -127,6 +138,13 @@ export function LiveEventBanner({
     }
   };
 
+  const dismissActiveToast = () => {
+    clearActiveTimer();
+    activeToastRef.current = null;
+    setActiveToast(null);
+    showNextToast();
+  };
+
   useEffect(() => {
     const currentSessionKey = sessionId ?? null;
     if (initializedSessionRef.current !== currentSessionKey) {
@@ -217,6 +235,15 @@ export function LiveEventBanner({
                       Retrying in {formatRetryCountdown(activeToast.next, toastNow)}
                     </div>
                   ) : null}
+                  <button
+                    type="button"
+                    className="oc-quick-input-icon-btn shrink-0 rounded p-1"
+                    title="Dismiss notification"
+                    aria-label="Dismiss notification"
+                    onClick={dismissActiveToast}
+                  >
+                    <X className="h-3.5 w-3.5" />
+                  </button>
                 </div>
                 {activeToast.message ? (
                   <div className={cn(
@@ -231,6 +258,3 @@ export function LiveEventBanner({
           </div>
         );
       })()}
-    </div>
-  );
-}