symfony
diff --git a/‎src/Symfony/Component/Routing/Loader/Configurator/Traits/PrefixTrait.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Routing/Loader/Configurator/Traits/PrefixTrait.php
+1Lines changed: 1 addition & 0 deletions b/‎src/Symfony/Component/Routing/Loader/Configurator/Traits/PrefixTrait.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Routing/Loader/Configurator/Traits/PrefixTrait.php
+1Lines changed: 1 addition & 0 deletions
@@ -33,6 +33,7 @@ final protected function addPrefix(RouteCollection $routes, $prefix, bool $trail
                     foreach ($prefix as $locale => $localePrefix) {
                         $localizedRoute = clone $route;
                         $localizedRoute->setDefault('_locale', $locale);
+                        $localizedRoute->setRequirement('_locale', preg_quote($locale));
                         $localizedRoute->setDefault('_canonical_route', $name);
                         $localizedRoute->setPath($localePrefix.(!$trailingSlashOnRoot && '/' === $route->getPath() ? '' : $route->getPath()));
                         $routes->add($name.'.'.$locale, $localizedRoute);