diff --git a/frontend/src/core/utils/homePageNavigation.test.ts b/frontend/src/core/utils/homePageNavigation.test.ts
index e6cadf79e..14b107aa3 100644
--- a/frontend/src/core/utils/homePageNavigation.test.ts
+++ b/frontend/src/core/utils/homePageNavigation.test.ts
@@ -25,21 +25,26 @@ describe('getStartupNavigationAction', () => {
     expect(getStartupNavigationAction(0, 3, 'pdfTextEditor', 'viewer' as WorkbenchType)).toBeNull();
   });
 
-  it('does not navigate on non-startup transitions', () => {
-    expect(getStartupNavigationAction(1, 2, null, 'viewer' as WorkbenchType)).toBeNull();
+  it('does not navigate when file count decreases', () => {
     expect(getStartupNavigationAction(2, 1, null, 'viewer' as WorkbenchType)).toBeNull();
+    expect(getStartupNavigationAction(3, 1, null, 'fileEditor' as WorkbenchType)).toBeNull();
   });
 
-  it('does not navigate when user already has files (N→M transitions)', () => {
-    // User has 1 file, adds another -> no navigation (stay in current workbench)
-    expect(getStartupNavigationAction(1, 2, null, 'viewer' as WorkbenchType)).toBeNull();
+  it('navigates to last file when already in viewer and files are added', () => {
+    expect(getStartupNavigationAction(1, 2, null, 'viewer' as WorkbenchType)).toEqual({
+      workbench: 'viewer',
+      activeFileIndex: 1,
+    });
+    expect(getStartupNavigationAction(3, 5, null, 'viewer' as WorkbenchType)).toEqual({
+      workbench: 'viewer',
+      activeFileIndex: 4,
+    });
+  });
+
+  it('does not navigate when adding files in non-viewer workbenches', () => {
     expect(getStartupNavigationAction(1, 2, null, 'fileEditor' as WorkbenchType)).toBeNull();
-
-    // User has 3 files, adds more -> no navigation
     expect(getStartupNavigationAction(3, 4, null, 'fileEditor' as WorkbenchType)).toBeNull();
-
-    // User has 2 files, deletes 1 -> no navigation
-    expect(getStartupNavigationAction(2, 1, null, 'viewer' as WorkbenchType)).toBeNull();
+    expect(getStartupNavigationAction(1, 3, null, 'pageEditor' as WorkbenchType)).toBeNull();
   });
 
   it('handles all workbench types consistently for 0→N transitions', () => {
diff --git a/frontend/src/core/utils/homePageNavigation.ts b/frontend/src/core/utils/homePageNavigation.ts
index 02f161643..cb3461e07 100644
--- a/frontend/src/core/utils/homePageNavigation.ts
+++ b/frontend/src/core/utils/homePageNavigation.ts
@@ -13,37 +13,25 @@ export function getStartupNavigationAction(
   selectedToolKey: string | null,
   currentWorkbench: WorkbenchType
 ): StartupNavigationAction | null {
-  console.log('[homePageNavigation] Called with:', {
-    previousFileCount,
-    currentFileCount,
-    selectedToolKey,
-    currentWorkbench,
-  });
-
   // pdfTextEditor handles its own empty state
   if (selectedToolKey === 'pdfTextEditor') {
-    console.log('[homePageNavigation] pdfTextEditor detected, returning null');
     return null;
   }
 
-  // Only handle transitions from empty (0 files) to some files
-  if (previousFileCount !== 0) {
-    console.log('[homePageNavigation] Not a 0→N transition, returning null');
-    return null;
+  // Already actively viewing in the viewer → update to the latest file
+  if (previousFileCount > 0 && currentWorkbench === 'viewer' && currentFileCount > previousFileCount) {
+    return { workbench: 'viewer', activeFileIndex: currentFileCount - 1 };
   }
 
-  // 0→1: Go to viewer to view the single file
-  if (currentFileCount === 1) {
-    console.log('[homePageNavigation] 0→1 transition, returning viewer');
-    return { workbench: 'viewer', activeFileIndex: 0 };
+  // From landing page (no prior files)
+  if (previousFileCount === 0) {
+    if (currentFileCount === 1) {
+      return { workbench: 'viewer', activeFileIndex: 0 };
+    }
+    if (currentFileCount > 1) {
+      return { workbench: 'fileEditor' };
+    }
   }
 
-  // 0→N (N>1): Go to fileEditor to manage multiple files
-  if (currentFileCount > 1) {
-    console.log('[homePageNavigation] 0→N transition, returning fileEditor');
-    return { workbench: 'fileEditor' };
-  }
-
-  console.log('[homePageNavigation] Still at 0 files, returning null');
   return null;
 }