diff --git a/Classes/EventListener/PageIndexer/FrontendGroupsModifier.php b/Classes/EventListener/PageIndexer/FrontendGroupsModifier.php
index 196063eac8..da9391d3ec 100644
--- a/Classes/EventListener/PageIndexer/FrontendGroupsModifier.php
+++ b/Classes/EventListener/PageIndexer/FrontendGroupsModifier.php
@@ -40,15 +40,20 @@ class FrontendGroupsModifier
     public function __invoke(ModifyResolvedFrontendGroupsEvent $event): void
     {
         $pageIndexerRequest = $event->getRequest()->getAttribute('solr.pageIndexingInstructions');
-        if (!$pageIndexerRequest instanceof PageIndexerRequest
-            || (
-                (int)$pageIndexerRequest->getParameter('userGroup') === 0
-                && (
-                    (int)$pageIndexerRequest->getParameter('pageUserGroup') !== -2
-                    &&
-                    (int)$pageIndexerRequest->getParameter('pageUserGroup') < 1
-                )
+        if (!$pageIndexerRequest instanceof PageIndexerRequest) {
+            return;
+        }
+
+        $groups = $this->resolveFrontendUserGroups($pageIndexerRequest);
+
+        $noRelevantFrontendUserGroupResolved = empty($groups) || (count($groups) === 1 && $groups[0] === 0);
+        if ((int)$pageIndexerRequest->getParameter('userGroup') === 0
+            && (
+                (int)$pageIndexerRequest->getParameter('pageUserGroup') !== -2
+                &&
+                (int)$pageIndexerRequest->getParameter('pageUserGroup') < 1
             )
+            && $noRelevantFrontendUserGroupResolved
         ) {
             return;
         }
@@ -76,7 +81,6 @@ public function __invoke(ModifyResolvedFrontendGroupsEvent $event): void
             );
         }
 
-        $groups = $this->resolveFrontendUserGroups($pageIndexerRequest);
         if ((int)$pageIndexerRequest->getParameter('pageUserGroup') > 0) {
             $groups[] = (int)$pageIndexerRequest->getParameter('pageUserGroup');
         }
diff --git a/Tests/Integration/IndexQueue/Fixtures/can_index_sub_page_of_protected_page_with_extend_to_subpage.csv b/Tests/Integration/IndexQueue/Fixtures/can_index_sub_page_of_protected_page_with_extend_to_subpage.csv
new file mode 100644
index 0000000000..58781e6318
--- /dev/null
+++ b/Tests/Integration/IndexQueue/Fixtures/can_index_sub_page_of_protected_page_with_extend_to_subpage.csv
@@ -0,0 +1,13 @@
+"fe_groups",
+,"uid","pid","title"
+,1,1,"group 1"
+"pages",
+,"uid","pid","is_siteroot","doktype","slug","title","subtitle","crdate","tstamp","fe_group",extendToSubpages
+,2,1,0,1,"/protected_page","protected page","",1449151778,1449151778,1,1
+,3,2,0,1,/sub_page,sub page, ,1449151779,1449151779,0,0
+"tt_content",
+,"uid","pid","CType","header","fe_group","sorting"
+,10,3,"header",public content of protected page,0,10
+"tx_solr_indexqueue_item",
+,"uid","root","item_type","item_uid","indexing_configuration","changed","indexed","has_indexing_properties","indexing_priority","indexed","errors"
+,4711,1,"pages",3,"pages",1449151778,0,0,0,0,0
diff --git a/Tests/Integration/IndexQueue/PageIndexerTest.php b/Tests/Integration/IndexQueue/PageIndexerTest.php
index 7ca8573e05..741444ec6b 100644
--- a/Tests/Integration/IndexQueue/PageIndexerTest.php
+++ b/Tests/Integration/IndexQueue/PageIndexerTest.php
@@ -202,6 +202,17 @@ public function canIndexPageWithAccessProtectedContentIntoSolrDataProvider(): Tr
                 'protected ce',
             ],
         ];
+
+        yield 'page protected by extend to subpages' => [
+            'can_index_sub_page_of_protected_page_with_extend_to_subpage',
+            1,
+            [
+                '2:1/c:0',
+            ],
+            [
+                'public content of protected page',
+            ],
+        ];
     }
 
     /**