Index: public/typo3/sysext/core/Classes/Routing/Aspect/SiteAccessorTrait.php
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- public/typo3/sysext/core/Classes/Routing/Aspect/SiteAccessorTrait.php	(date 1589627176357)
+++ public/typo3/sysext/core/Classes/Routing/Aspect/SiteAccessorTrait.php	(date 1589627176357)
@@ -76,7 +76,11 @@
                 // default FrontendRestrictionContainer retrieves only live records
                 // (no specific workspace & move-placeholder resolving required here)
                 $pageId = (int)$result['pid'];
-                return $this->isPageIdContainedInSite($pageId);
+                if ($this->isPageInsideOfRealSite($pageId)) {
+                    return $this->isPageIdContainedInSite($pageId);
+                } else {
+                    return true;
+                }
             }
         );
     }
@@ -105,4 +109,15 @@
         }
         return $this->siteMatcher;
     }
+
+    /**
+     * @param int $pageUid
+     * @return bool
+     */
+    protected function isPageInsideOfRealSite(int $pageUid): bool
+    {
+        $expectedSite = $this->getSiteMatcher()->matchByPageId($pageUid);
+
+        return $expectedSite instanceof Site;
+    }
 }