#1203699034: A cache with identifier „extbase_object“ does not exist.
Die Lösung:
In der LocalConfiguration.php muss unter [‚SYS‘][‚caching‘][‚cacheConfigurations‘] folgendes ergänzt werden:
'extbase_object' => [
'backend' => 'TYPO3\\CMS\\Core\\Cache\\Backend\\Typo3DatabaseBackend',
'frontend' => 'TYPO3\\CMS\\Core\\Cache\\Frontend\\VariableFrontend',
'groups' => [
'system',
],
'options' => [
'defaultLifetime' => 0,
],
],