diff --git a/src/calibre/gui2/viewer/toc.py b/src/calibre/gui2/viewer/toc.py
index 991e6563f2..9289d6362b 100644
--- a/src/calibre/gui2/viewer/toc.py
+++ b/src/calibre/gui2/viewer/toc.py
@@ -113,8 +113,8 @@ class TOCView(QTreeView):
         m = self.model()
         QApplication.clipboard().setText(getattr(m, 'as_plain_text', ''))
 
-    def update_current_toc_nodes(self, current_node_id, toplevel_node_id):
-        self.model().update_current_toc_nodes(current_node_id, toplevel_node_id)
+    def update_current_toc_nodes(self, families):
+        self.model().update_current_toc_nodes(families)
 
 
 class TOCSearch(QWidget):
@@ -248,13 +248,19 @@ class TOC(QStandardItemModel):
             return index
         return QModelIndex()
 
-    def update_current_toc_nodes(self, current_node_id, top_level_node_id):
-        node = self.node_id_map.get(current_node_id)
+    def update_current_toc_nodes(self, current_toc_leaves):
         viewed_nodes = set()
-        if node is not None:
-            viewed_nodes |= {x.node_id for x in node.ancestors}
-            viewed_nodes.add(node.node_id)
-            self.auto_expand_nodes.emit([n.index() for n in node.ancestors])
+        ancestors = {}
+        for node_id in current_toc_leaves:
+            node = self.node_id_map.get(node_id)
+            if node is not None:
+                viewed_nodes.add(node_id)
+                ansc = tuple(node.ancestors)
+                viewed_nodes |= {x.node_id for x in ansc}
+                for x in ansc:
+                    ancestors[x.node_id] = x.index()
+        if ancestors:
+            self.auto_expand_nodes.emit(tuple(ancestors.values()))
         for node in self.all_items:
             is_being_viewed = node.node_id in viewed_nodes
             if is_being_viewed != node.is_being_viewed:
diff --git a/src/calibre/gui2/viewer/web_view.py b/src/calibre/gui2/viewer/web_view.py
index c373340d9d..9b54b7679c 100644
--- a/src/calibre/gui2/viewer/web_view.py
+++ b/src/calibre/gui2/viewer/web_view.py
@@ -250,7 +250,7 @@ class ViewerBridge(Bridge):
     search_result_not_found = from_js(object)
     find_next = from_js(object)
     quit = from_js()
-    update_current_toc_nodes = from_js(object, object)
+    update_current_toc_nodes = from_js(object)
     toggle_full_screen = from_js()
     report_cfi = from_js(object, object)
     ask_for_open = from_js(object)
@@ -456,7 +456,7 @@ class WebView(RestartingWebEngineView):
     toggle_inspector = pyqtSignal()
     toggle_lookup = pyqtSignal(object)
     quit = pyqtSignal()
-    update_current_toc_nodes = pyqtSignal(object, object)
+    update_current_toc_nodes = pyqtSignal(object)
     toggle_full_screen = pyqtSignal()
     ask_for_open = pyqtSignal(object)
     selection_changed = pyqtSignal(object, object)
diff --git a/src/pyj/read_book/toc.pyj b/src/pyj/read_book/toc.pyj
index 35fe63d93f..451ba4364d 100644
--- a/src/pyj/read_book/toc.pyj
+++ b/src/pyj/read_book/toc.pyj
@@ -100,10 +100,12 @@ def get_current_toc_nodes():
             before = get_border_nodes(toc, id_map)[0]
             if before:
                 ans[before.id] = True
-    ans = Object.keys(ans)
-    if ans.length:
-        return family_for_toc_node(ans[0], parent_map, id_map)
-    return v'[]'
+    r = v'[]'
+    for x in Object.keys(ans):
+        fam = family_for_toc_node(x, parent_map, id_map)
+        if fam?.length:
+            r.push(fam)
+    return r
 
 
 def get_highlighted_toc_nodes(toc, parent_map, id_map):
diff --git a/src/pyj/read_book/view.pyj b/src/pyj/read_book/view.pyj
index 89534eca3d..c5951c28d7 100644
--- a/src/pyj/read_book/view.pyj
+++ b/src/pyj/read_book/view.pyj
@@ -210,7 +210,7 @@ class View:
         self.current_progress_frac = self.current_file_progress_frac = 0
         self.current_page_counts = {'current': 0, 'total': 0, 'pages_per_screen': 1}
         self.current_toc_node = self.current_toc_toplevel_node = None
-        self.current_toc_family = v'[]'
+        self.current_toc_families = v'[]'
         self.report_cfi_callbacks = {}
         self.get_cfi_counter = 0
         self.show_loading_callback_timer = None
@@ -1293,14 +1293,19 @@ class View:
 
     def on_update_toc_position(self, data):
         update_visible_toc_nodes(data.visible_anchors)
-        self.current_toc_family = get_current_toc_nodes()
-        if self.current_toc_family.length:
-            self.current_toc_node = self.current_toc_family[-1]
-            self.current_toc_toplevel_node = self.current_toc_family[0]
+        self.current_toc_families = get_current_toc_nodes()
+        if self.current_toc_families.length:
+            first = self.current_toc_families[0]
+            self.current_toc_node = first[-1]
+            self.current_toc_toplevel_node = first[0]
         else:
             self.current_toc_node = self.current_toc_toplevel_node = None
         if runtime.is_standalone_viewer:
-            ui_operations.update_current_toc_nodes(self.current_toc_node?.id, self.current_toc_toplevel_node?.id)
+            r = v'[]'
+            for fam in self.current_toc_families:
+                if fam.length:
+                    r.push(fam[-1].id)
+            ui_operations.update_current_toc_nodes(r)
         self.update_header_footer()
 
     def show_spine_item(self, resource_data):
diff --git a/src/pyj/viewer-main.pyj b/src/pyj/viewer-main.pyj
index 5c59dc24a9..0b76e4b711 100644
--- a/src/pyj/viewer-main.pyj
+++ b/src/pyj/viewer-main.pyj
@@ -365,8 +365,8 @@ if window is window.top:
         to_python.toggle_lookup(v'!!force_show')
     ui_operations.selection_changed = def(selected_text, annot_id):
         to_python.selection_changed(selected_text, annot_id or None)
-    ui_operations.update_current_toc_nodes = def(current_node_id, top_level_node_id):
-        to_python.update_current_toc_nodes(current_node_id, top_level_node_id)
+    ui_operations.update_current_toc_nodes = def(families):
+        to_python.update_current_toc_nodes(families)
     ui_operations.toggle_full_screen = def():
         to_python.toggle_full_screen()
     ui_operations.report_cfi = def(request_id, data):