diff --git a/src/DependencyInjection/MonologExtension.php b/src/DependencyInjection/MonologExtension.php
index b57c31f9..5193a672 100644
--- a/src/DependencyInjection/MonologExtension.php
+++ b/src/DependencyInjection/MonologExtension.php
@@ -19,10 +19,8 @@
 use Monolog\Processor\PsrLogMessageProcessor;
 use Monolog\ResettableInterface;
 use Symfony\Bridge\Monolog\Handler\FingersCrossed\HttpCodeActivationStrategy;
-use Symfony\Bridge\Monolog\Logger as LegacyLogger;
 use Symfony\Bridge\Monolog\Processor\SwitchUserTokenProcessor;
 use Symfony\Bridge\Monolog\Processor\TokenProcessor;
-use Symfony\Bridge\Monolog\Processor\WebProcessor;
 use Symfony\Component\Config\FileLocator;
 use Symfony\Component\DependencyInjection\Argument\BoundArgument;
 use Symfony\Component\DependencyInjection\ChildDefinition;
@@ -31,7 +29,6 @@
 use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\HttpKernel\DependencyInjection\Extension;
-use Symfony\Component\HttpKernel\Log\DebugLoggerConfigurator;
 use Symfony\Contracts\HttpClient\HttpClientInterface;
 
 /**
@@ -39,10 +36,8 @@
  *
  * @author Jordi Boggiano <j.boggiano@seld.be>
  * @author Christophe Coevoet <stof@notk.org>
- *
- * @final since 3.9.0
  */
-class MonologExtension extends Extension
+final class MonologExtension extends Extension
 {
     private $nestedHandlers = [];
 
@@ -61,10 +56,6 @@ public function load(array $configs, ContainerBuilder $container)
             $loader = new PhpFileLoader($container, new FileLocator(__DIR__.'/../../config'));
             $loader->load('monolog.php');
 
-            if (!class_exists(DebugLoggerConfigurator::class)) {
-                $container->getDefinition('monolog.logger_prototype')->setClass(LegacyLogger::class);
-            }
-
             $container->setParameter('monolog.use_microseconds', $config['use_microseconds']);
 
             $handlers = [];
@@ -95,19 +86,13 @@ public function load(array $configs, ContainerBuilder $container)
 
         $container->setParameter('monolog.additional_channels', $config['channels'] ?? []);
 
-        if (interface_exists(ProcessorInterface::class)) {
-            $container->registerForAutoconfiguration(ProcessorInterface::class)
-                ->addTag('monolog.processor');
-        } else {
-            $container->registerForAutoconfiguration(WebProcessor::class)
-                ->addTag('monolog.processor');
-        }
-        if (interface_exists(ResettableInterface::class)) {
-            $container->registerForAutoconfiguration(ResettableInterface::class)
-                ->addTag('kernel.reset', ['method' => 'reset']);
-        }
+        $container->registerForAutoconfiguration(ProcessorInterface::class)
+            ->addTag('monolog.processor');
+        $container->registerForAutoconfiguration(ResettableInterface::class)
+            ->addTag('kernel.reset', ['method' => 'reset']);
         $container->registerForAutoconfiguration(TokenProcessor::class)
             ->addTag('monolog.processor');
+
         if (interface_exists(HttpClientInterface::class)) {
             $handlerAutoconfiguration = $container->registerForAutoconfiguration(HandlerInterface::class);
             $handlerAutoconfiguration->setBindings($handlerAutoconfiguration->getBindings() + [
@@ -115,23 +100,21 @@ public function load(array $configs, ContainerBuilder $container)
             ]);
         }
 
-        if (80000 <= \PHP_VERSION_ID) {
-            $container->registerAttributeForAutoconfiguration(AsMonologProcessor::class, static function (ChildDefinition $definition, AsMonologProcessor $attribute, \Reflector $reflector): void {
-                $tagAttributes = get_object_vars($attribute);
-                if ($reflector instanceof \ReflectionMethod) {
-                    if (isset($tagAttributes['method'])) {
-                        throw new \LogicException(\sprintf('AsMonologProcessor attribute cannot declare a method on "%s::%s()".', $reflector->class, $reflector->name));
-                    }
-
-                    $tagAttributes['method'] = $reflector->getName();
+        $container->registerAttributeForAutoconfiguration(AsMonologProcessor::class, static function (ChildDefinition $definition, AsMonologProcessor $attribute, \Reflector $reflector): void {
+            $tagAttributes = get_object_vars($attribute);
+            if ($reflector instanceof \ReflectionMethod) {
+                if (isset($tagAttributes['method'])) {
+                    throw new \LogicException(\sprintf('AsMonologProcessor attribute cannot declare a method on "%s::%s()".', $reflector->class, $reflector->name));
                 }
 
-                $definition->addTag('monolog.processor', $tagAttributes);
-            });
-            $container->registerAttributeForAutoconfiguration(WithMonologChannel::class, static function (ChildDefinition $definition, WithMonologChannel $attribute): void {
-                $definition->addTag('monolog.logger', ['channel' => $attribute->channel]);
-            });
-        }
+                $tagAttributes['method'] = $reflector->getName();
+            }
+
+            $definition->addTag('monolog.processor', $tagAttributes);
+        });
+        $container->registerAttributeForAutoconfiguration(WithMonologChannel::class, static function (ChildDefinition $definition, WithMonologChannel $attribute): void {
+            $definition->addTag('monolog.logger', ['channel' => $attribute->channel]);
+        });
     }
 
     /**
@@ -899,23 +882,12 @@ private function getHandlerClassByType($handlerType)
 
     private function buildPsrLogMessageProcessor(ContainerBuilder $container, array $processorOptions): string
     {
-        static $hasConstructorArguments;
-
-        if (!isset($hasConstructorArguments)) {
-            $reflectionConstructor = (new \ReflectionClass(PsrLogMessageProcessor::class))->getConstructor();
-            $hasConstructorArguments = null !== $reflectionConstructor && $reflectionConstructor->getNumberOfParameters() > 0;
-            unset($reflectionConstructor);
-        }
-
         $processorId = 'monolog.processor.psr_log_message';
         $processorArguments = [];
 
         unset($processorOptions['enabled']);
 
-        if (!empty($processorOptions)) {
-            if (!$hasConstructorArguments) {
-                throw new \RuntimeException('Monolog 1.26 or higher is required for the "date_format" and "remove_used_context_fields" options to be used.');
-            }
+        if ($processorOptions) {
             $processorArguments = [
                 $processorOptions['date_format'] ?? null,
                 $processorOptions['remove_used_context_fields'] ?? false,