diff --git a/packages/ui/src/components/session/SessionSidebar.tsx b/packages/ui/src/components/session/SessionSidebar.tsx
index 2f01034f..57a851fe 100644
--- a/packages/ui/src/components/session/SessionSidebar.tsx
+++ b/packages/ui/src/components/session/SessionSidebar.tsx
@@ -81,7 +81,13 @@ const PROJECT_COLLAPSE_STORAGE_KEY = 'oc.sessions.projectCollapse';
 const GROUP_ORDER_STORAGE_KEY = 'oc.sessions.groupOrder';
 const GROUP_COLLAPSE_STORAGE_KEY = 'oc.sessions.groupCollapse';
 const PROJECT_ACTIVE_SESSION_STORAGE_KEY = 'oc.sessions.activeSessionByProject';
-const SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents';
+// v2 key holds composite "${renderContext}:${active|archived}:${sessionId}"
+// entries so the same session in different render contexts (e.g. "Recent"
+// and a project's root) has independent expand state. v1 held bare session
+// ids; useSidebarPersistence migrates v1 data on first read by fanning each
+// id into all four context combinations.
+const SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents.v2';
+const LEGACY_SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents';
 const SESSION_PINNED_STORAGE_KEY = 'oc.sessions.pinned';
 
 type PrVisualState = 'draft' | 'open' | 'blocked' | 'merged' | 'closed';
@@ -521,6 +527,7 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     safeStorage,
     keys: {
       sessionExpanded: SESSION_EXPANDED_STORAGE_KEY,
+      sessionExpandedLegacy: LEGACY_SESSION_EXPANDED_STORAGE_KEY,
       projectCollapse: PROJECT_COLLAPSE_STORAGE_KEY,
       sessionPinned: SESSION_PINNED_STORAGE_KEY,
       groupOrder: GROUP_ORDER_STORAGE_KEY,
@@ -677,16 +684,25 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     sessionEvents.requestDirectoryDialog();
   }, []);
 
-  // Auto-expand parent session when navigating to a subagent (child) session
+  // Auto-expand parent session when navigating to a subagent (child) session.
+  // We don't know which render context the user will look at the parent in
+  // (Recent, project root, archived bucket, ...), so fan out across all
+  // four combinations to ensure it's expanded wherever it appears.
   React.useEffect(() => {
     if (!currentSessionId) return;
     const current = sessions.find((s) => s.id === currentSessionId);
     const parentID = (current as Session & { parentID?: string | null })?.parentID;
     if (!parentID) return;
+    const keysToAdd = [
+      `project:active:${parentID}`,
+      `project:archived:${parentID}`,
+      `recent:active:${parentID}`,
+      `recent:archived:${parentID}`,
+    ];
     setExpandedParents((prev) => {
-      if (prev.has(parentID)) return prev;
+      if (keysToAdd.every((k) => prev.has(k))) return prev;
       const next = new Set(prev);
-      next.add(parentID);
+      keysToAdd.forEach((k) => next.add(k));
       try {
         safeStorage.setItem(SESSION_EXPANDED_STORAGE_KEY, JSON.stringify(Array.from(next)));
       } catch { /* ignored */ }
@@ -694,13 +710,13 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     });
   }, [currentSessionId, sessions, safeStorage]);
 
-  const toggleParent = React.useCallback((sessionId: string) => {
+  const toggleParent = React.useCallback((expansionKey: string) => {
     setExpandedParents((prev) => {
       const next = new Set(prev);
-      if (next.has(sessionId)) {
-        next.delete(sessionId);
+      if (next.has(expansionKey)) {
+        next.delete(expansionKey);
       } else {
-        next.add(sessionId);
+        next.add(expansionKey);
       }
       try {
         safeStorage.setItem(SESSION_EXPANDED_STORAGE_KEY, JSON.stringify(Array.from(next)));
diff --git a/packages/ui/src/components/session/sidebar/SessionNodeItem.tsx b/packages/ui/src/components/session/sidebar/SessionNodeItem.tsx
index 093beccd..63895a2a 100644
--- a/packages/ui/src/components/session/sidebar/SessionNodeItem.tsx
+++ b/packages/ui/src/components/session/sidebar/SessionNodeItem.tsx
@@ -59,7 +59,7 @@ type Props = {
   setEditTitle: (value: string) => void;
   handleSaveEdit: () => void;
   handleCancelEdit: () => void;
-  toggleParent: (sessionId: string) => void;
+  toggleParent: (expansionKey: string) => void;
   handleSessionSelect: (sessionId: string, sessionDirectory: string | null, isMissingDirectory: boolean, projectId?: string | null) => void;
   handleSessionDoubleClick: () => void;
   togglePinnedSession: (sessionId: string) => void;
@@ -157,7 +157,18 @@ const areEqual = (prev: Props, next: Props): boolean => {
     }
   }
   if (prev.pinnedSessionIds.has(prevSessionId) !== next.pinnedSessionIds.has(nextSessionId)) return false;
-  if (prev.expandedParents.has(prevSessionId) !== next.expandedParents.has(nextSessionId)) return false;
+  // Expansion is keyed per render context, so compare the composite key
+  // matching the one isExpanded reads from in render. If a session appears
+  // in two contexts (project + recent), they have independent state.
+  {
+    const prevRenderContext = prev.renderContext ?? 'project';
+    const nextRenderContext = next.renderContext ?? 'project';
+    const prevArchived = prev.archivedBucket ?? false;
+    const nextArchived = next.archivedBucket ?? false;
+    const prevExpansionKey = `${prevRenderContext}:${prevArchived ? 'archived' : 'active'}:${prevSessionId}`;
+    const nextExpansionKey = `${nextRenderContext}:${nextArchived ? 'archived' : 'active'}:${nextSessionId}`;
+    if (prev.expandedParents.has(prevExpansionKey) !== next.expandedParents.has(nextExpansionKey)) return false;
+  }
   if (prev.hasSessionSearchQuery !== next.hasSessionSearchQuery) return false;
   if (prev.normalizedSessionSearchQuery !== next.normalizedSessionSearchQuery) return false;
   if (prev.notifyOnSubtasks !== next.notifyOnSubtasks) return false;
@@ -312,7 +323,11 @@ function SessionNodeItemComponent(props: Props): React.ReactNode {
   const sessionTitle = resolvedSession.title || t('sessions.sidebar.session.untitled');
   const hasChildren = node.children.length > 0;
   const isPinnedSession = pinnedSessionIds.has(session.id);
-  const isExpanded = hasSessionSearchQuery ? true : expandedParents.has(session.id);
+  // Per-render-context expansion key: the same session can appear in both
+  // the project's root and the "Recent" list, and expanding one should not
+  // expand the other. Matches the format of menuInstanceKey.
+  const expansionKey = menuInstanceKey;
+  const isExpanded = hasSessionSearchQuery ? true : expandedParents.has(expansionKey);
   const isSubtaskSession = Boolean((resolvedSession as Session & { parentID?: string | null }).parentID);
   const unseenCount = useSessionUnseenCount(session.id);
   const needsAttention = unseenCount > 0 && (!isSubtaskSession || notifyOnSubtasks);
@@ -529,13 +544,13 @@ function SessionNodeItemComponent(props: Props): React.ReactNode {
       tabIndex={0}
       onClick={(event) => {
         event.stopPropagation();
-        toggleParent(session.id);
+        toggleParent(expansionKey);
       }}
       onKeyDown={(event) => {
         if (event.key === 'Enter' || event.key === ' ') {
           event.preventDefault();
           event.stopPropagation();
-          toggleParent(session.id);
+          toggleParent(expansionKey);
         }
       }}
       className={cn(
diff --git a/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
index 668fa478..6faf5503 100644
--- a/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
+++ b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
@@ -6,10 +6,16 @@ import { useProjectsStore } from '@/stores/useProjectsStore';
 type SafeStorageLike = {
   getItem: (key: string) => string | null;
   setItem: (key: string, value: string) => void;
+  removeItem?: (key: string) => void;
 };
 
 type Keys = {
   sessionExpanded: string;
+  // v1 key, still on disk for users upgrading from pre-per-context expansion.
+  // When present, its bare-session-id entries are fanned out to all four
+  // (project|recent) × (active|archived) context combinations and rewritten
+  // under `sessionExpanded`. After migration the v1 key is removed.
+  sessionExpandedLegacy: string;
   projectCollapse: string;
   sessionPinned: string;
   groupOrder: string;
@@ -17,6 +23,13 @@ type Keys = {
   groupCollapse: string;
 };
 
+const LEGACY_EXPANSION_CONTEXT_PREFIXES = [
+  'project:active:',
+  'project:archived:',
+  'recent:active:',
+  'recent:archived:',
+];
+
 type Args = {
   isVSCode: boolean;
   hasLoadedGlobalSessions: boolean;
@@ -101,6 +114,28 @@ export const useSidebarPersistence = (args: Args) => {
         if (Array.isArray(parsed)) {
           setExpandedParents(new Set(parsed.filter((item) => typeof item === 'string')));
         }
+      } else {
+        // No v2 data — migrate from v1 (bare session ids) if present.
+        const legacyRaw = safeStorage.getItem(keys.sessionExpandedLegacy);
+        if (legacyRaw) {
+          try {
+            const parsedLegacy = JSON.parse(legacyRaw);
+            if (Array.isArray(parsedLegacy)) {
+              const migrated = new Set<string>();
+              parsedLegacy.forEach((item) => {
+                if (typeof item !== 'string' || item.length === 0) return;
+                LEGACY_EXPANSION_CONTEXT_PREFIXES.forEach((prefix) => migrated.add(`${prefix}${item}`));
+              });
+              if (migrated.size > 0) {
+                setExpandedParents(migrated);
+                try { safeStorage.setItem(keys.sessionExpanded, JSON.stringify(Array.from(migrated))); } catch { /* ignored */ }
+              }
+            }
+          } catch {
+            // legacy data was malformed; ignore and let it expire
+          }
+          try { safeStorage.removeItem?.(keys.sessionExpandedLegacy); } catch { /* ignored */ }
+        }
       }
       const storedProjects = safeStorage.getItem(keys.projectCollapse);
       if (storedProjects) {
@@ -112,7 +147,7 @@ export const useSidebarPersistence = (args: Args) => {
     } catch {
       // ignored
     }
-  }, [keys.projectCollapse, keys.sessionExpanded, safeStorage, setCollapsedProjects, setExpandedParents]);
+  }, [keys.projectCollapse, keys.sessionExpanded, keys.sessionExpandedLegacy, safeStorage, setCollapsedProjects, setExpandedParents]);
 
   React.useEffect(() => {
     if (!hasLoadedGlobalSessions) {