SPI cache methods which use \eZ\Publish\Core\Persistence\Cache\AbstractHandler::getMultipleCacheItems internally logs calls for missing items as

FQCN\{closure}

e.g.

\eZ\Publish\Core\Persistence\Cache\BookmarkHandler\{closure}

instead of real SPI method name e.g

\eZ\Publish\Core\Persistence\Cache\BookmarkHandler::loadByUserIdAndLocationId

which at the end cause "Notice: Undefined offset: 1" error when eZ Platform tab is open in the Symfony Profiler