Unexpected error too few arguments after update to 8.x-2.8

Same here.

I can report the same error; I'm also on Drupal 9.5.

[13-Sep-2023 22:53:59 UTC] ArgumentCountError: Too few arguments to function Drupal\mail_login\AuthDecorator::__construct(), 3 passed in /var/www/html/docroot/core/lib/Drupal/Component/DependencyInjection/Container.php on line 259 and exactly 5 expected in /var/www/html/docroot/modules/contrib/mail_login/src/AuthDecorator.php on line 69 #0 /var/www/html/docroot/core/lib/Drupal/Component/DependencyInjection/Container.php(259): Drupal\mail_login\AuthDecorator->__construct()
#1 /var/www/html/docroot/core/lib/Drupal/Component/DependencyInjection/Container.php(177): Drupal\Component\DependencyInjection\Container->createService()
#2 /var/www/html/docroot/core/modules/user/src/Form/UserLoginForm.php(95): Drupal\Component\DependencyInjection\Container->get()
#3 /var/www/html/docroot/core/lib/Drupal/Core/DependencyInjection/ClassResolver.php(28): Drupal\user\Form\UserLoginForm::create()
#4 /var/www/html/docroot/core/lib/Drupal/Core/Form/FormBuilder.php(195): Drupal\Core\DependencyInjection\ClassResolver->getInstanceFromDefinition()
#5 /var/www/html/docroot/core/lib/Drupal/Core/Form/FormBuilder.php(232): Drupal\Core\Form\FormBuilder->getFormId()
#6 /var/www/html/docroot/core/lib/Drupal/Core/Form/FormBuilder.php(224): Drupal\Core\Form\FormBuilder->buildForm()
#7 /var/www/html/docroot/themes/my_theme/my_theme.theme(71): Drupal\Core\Form\FormBuilder->getForm()
#8 [internal function]: my_theme_preprocess_node()
#9 /var/www/html/docroot/core/lib/Drupal/Core/Theme/ThemeManager.php(287): call_user_func_array()
#10 /var/www/html/docroot/core/lib/Drupal/Core/Render/Renderer.php(433): Drupal\Core\Theme\ThemeManager->render()
#11 /var/www/html/docroot/core/lib/Drupal/Core/Render/Renderer.php(204): Drupal\Core\Render\Renderer->doRender()
#12 /var/www/html/docroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(242): Drupal\Core\Render\Renderer->render()
#13 /var/www/html/docroot/core/lib/Drupal/Core/Render/Renderer.php(580): Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}()
#14 /var/www/html/docroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(243): Drupal\Core\Render\Renderer->executeInRenderContext()
#15 /var/www/html/docroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(132): Drupal\Core\Render\MainContent\HtmlRenderer->prepare()
#16 /var/www/html/docroot/core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php(90): Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse()
#17 [internal function]: Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray()
#18 /var/www/html/docroot/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(142): call_user_func()
#19 /var/www/html/docroot/vendor/symfony/http-kernel/HttpKernel.php(174): Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch()
#20 /var/www/html/docroot/vendor/symfony/http-kernel/HttpKernel.php(81): Symfony\Component\HttpKernel\HttpKernel->handleRaw()
#21 /var/www/html/docroot/core/lib/Drupal/Core/StackMiddleware/Session.php(58): Symfony\Component\HttpKernel\HttpKernel->handle()
#22 /var/www/html/docroot/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle()
#23 /var/www/html/docroot/core/modules/page_cache/src/StackMiddleware/PageCache.php(191): Drupal\Core\StackMiddleware\KernelPreHandle->handle()
#24 /var/www/html/docroot/core/modules/page_cache/src/StackMiddleware/PageCache.php(128): Drupal\page_cache\StackMiddleware\PageCache->fetch()
#25 /var/www/html/docroot/core/modules/page_cache/src/StackMiddleware/PageCache.php(82): Drupal\page_cache\StackMiddleware\PageCache->lookup()
#26 /var/www/html/docroot/core/modules/ban/src/BanMiddleware.php(50): Drupal\page_cache\StackMiddleware\PageCache->handle()
#27 /var/www/html/docroot/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\ban\BanMiddleware->handle()
#28 /var/www/html/docroot/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle()
#29 /var/www/html/docroot/vendor/stack/builder/src/Stack/StackedHttpKernel.php(23): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle()
#30 /var/www/html/docroot/core/lib/Drupal/Core/DrupalKernel.php(718): Stack\StackedHttpKernel->handle()
#31 /var/www/html/docroot/index.php(19): Drupal\Core\DrupalKernel->handle()
#32 {main} request_id="v-6cfcba98-5288-11ee-9e20-8302e64bd82a"

I'm working on a fix for the reported issue, will be available soon in the latest dev branch.

After a vendor/bin/drush cr the error goes away. At least for me.

Looks like this was caused by the fix for issue 3342236, which increased the number of arguments from 3 to 5.
See https://git.drupalcode.org/project/mail_login/-/commit/929c4fa94a9cc2c11...

@mqanneh Is there something we can do to help you with a fix? My sites are nagging me about a security update that I cannot install.

This affects a security release.

This is a patch for 8.x-2.7 that contains only the code for the flood control.

I see there is a new declaration for routing "user.login" in mail_login.routing.yml, but there is no controller or somthing handler for this routing to overwrite the core routing. So can someone explain to me what adding routing and new form MailLoginUserLoginForm is for?

Fixed in https://www.drupal.org/project/mail_login/releases/8.x-2.9