[BUGFIX] Fix missing frontend.typoscript request attribute while inde…

…xing

Fixes: #3751

Classes/FrontendEnvironment/Tsfe.php

@@ -168,10 +168,9 @@ protected function initializeTsfe(int $pageId, int $language = 0, ?int $rootPage
             $backedUpBackendUser = $GLOBALS['BE_USER'] ?? null;
             try {
                 $tsfe->determineId($serverRequest);
-                $serverRequest->withAttribute('frontend.controller', $tsfe);
+                $serverRequest = $serverRequest->withAttribute('frontend.controller', $tsfe);
                 $tsfe->no_cache = false;
-                // @todo T12: Check if following line really needed
-                $tsfe->getFromCache($serverRequest);
+                $serverRequest = $tsfe->getFromCache($serverRequest);
                 // The manual releasing of locks is low level api and should be avoided in EXT:solr.
                 $tsfe->releaseLocks();
 
@@ -193,6 +192,7 @@ protected function initializeTsfe(int $pageId, int $language = 0, ?int $rootPage
                 $GLOBALS['BE_USER'] = $backedUpBackendUser;
             }
 
+            $this->serverRequestCache[$cacheIdentifier] = $serverRequest;
             $this->tsfeCache[$cacheIdentifier] = $tsfe;
         }