Bug fixes
[f72bc2e] Remove prefix from URL to match in AdminRouterSubscriber::getSymfonyControllerFqcn (@pacproduct)
[da8f4e2] Use the Twig guard tag to handle optional functions/filters (@javiereguiluz)
[e9f8ee6] Fix remaining calls to deprecated getReferrer()
method (@AirBair)
[e128cf7] [Doc] Fix typo in route attribute (@elliotbruneel)