Class Elbformat\IconBundle\DependencyInjection\Configuration implements unknown interface Symfony\Component\Config\Definition\ConfigurationInterface.

Method Elbformat\IconBundle\DependencyInjection\Configuration::getConfigTreeBuilder() has invalid return type Symfony\Component\Config\Definition\Builder\TreeBuilder.

Instantiated class Symfony\Component\Config\Definition\Builder\TreeBuilder not found.

Class Elbformat\IconBundle\DependencyInjection\ElbformatIconExtension extends unknown class Symfony\Component\DependencyInjection\Extension\Extension.

Class Elbformat\IconBundle\DependencyInjection\ElbformatIconExtension implements unknown interface Symfony\Component\DependencyInjection\Extension\PrependExtensionInterface.

Parameter $container of method Elbformat\IconBundle\DependencyInjection\ElbformatIconExtension::load() has invalid type Symfony\Component\DependencyInjection\ContainerBuilder.

Instantiated class Symfony\Component\Config\FileLocator not found.

Instantiated class Symfony\Component\DependencyInjection\Loader\YamlFileLoader not found.

Call to method load() on an unknown class Symfony\Component\DependencyInjection\Loader\YamlFileLoader.