here is the log trace when using the rainlab mailchimp plugin. A user is entering his email in the input field and click submit, which throws this exception in the vdlp 2fa plugin as per the log below. Any idea what could happen here?

October\Rain\Exception\SystemException: A widget with class name 'listFilter' has not been bound to the controller in /var/www/html/modules/backend/classes/Controller.php:607
Stack trace:
#0 /var/www/html/modules/backend/classes/Controller.php(452): Backend\Classes\Controller->runAjaxHandler()
#1 /var/www/html/modules/backend/classes/Controller.php(260): Backend\Classes\Controller->execAjaxHandlers()
#2 /var/www/html/modules/backend/classes/BackendController.php(98): Backend\Classes\Controller->run()
#3 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Controller.php(54): Backend\Classes\BackendController->run()
#4 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php(43): Illuminate\Routing\Controller->callAction()
#5 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Route.php(260): Illuminate\Routing\ControllerDispatcher->dispatch()
#6 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Route.php(205): Illuminate\Routing\Route->runController()
#7 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Router.php(798): Illuminate\Routing\Route->run()
#8 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(141): Illuminate\Routing\Router->Illuminate\Routing\{closure}()
#9 /var/www/html/plugins/vdlp/twofactorauthentication/classes/TwoFactorMiddleware.php(57): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#10 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Vdlp\TwoFactorAuthentication\Classes\TwoFactorMiddleware->handle()
#11 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php(50): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#12 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Routing\Middleware\SubstituteBindings->handle()
#13 /var/www/html/vendor/laravel/framework/src/Illuminate/View/Middleware/ShareErrorsFromSession.php(49): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#14 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\View\Middleware\ShareErrorsFromSession->handle()
#15 /var/www/html/vendor/laravel/framework/src/Illuminate/Session/Middleware/StartSession.php(121): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#16 /var/www/html/vendor/laravel/framework/src/Illuminate/Session/Middleware/StartSession.php(64): Illuminate\Session\Middleware\StartSession->handleStatefulRequest()
#17 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Session\Middleware\StartSession->handle()
#18 /var/www/html/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/AddQueuedCookiesToResponse.php(37): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#19 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse->handle()
#20 /var/www/html/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php(67): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#21 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Cookie\Middleware\EncryptCookies->handle()
#22 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(116): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#23 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Router.php(799): Illuminate\Pipeline\Pipeline->then()
#24 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Router.php(776): Illuminate\Routing\Router->runRouteWithinStack()
#25 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Router.php(740): Illuminate\Routing\Router->runRoute()
#26 /var/www/html/vendor/october/rain/src/Router/CoreRouter.php(32): Illuminate\Routing\Router->dispatchToRoute()
#27 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(190): October\Rain\Router\CoreRouter->dispatch()
#28 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(141): Illuminate\Foundation\Http\Kernel->Illuminate\Foundation\Http\{closure}()
#29 /var/www/html/plugins/zaxbux/securityheaders/classes/SecurityHeaderMiddleware.php(20): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#30 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Zaxbux\SecurityHeaders\Classes\SecurityHeaderMiddleware->handle()
#31 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/PreventRequestsDuringMaintenance.php(86): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#32 /var/www/html/vendor/october/rain/src/Foundation/Http/Middleware/CheckForMaintenanceMode.php(23): Illuminate\Foundation\Http\Middleware\PreventRequestsDuringMaintenance->handle()
#33 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): October\Rain\Foundation\Http\Middleware\CheckForMaintenanceMode->handle()
#34 /var/www/html/plugins/zaxbux/securityheaders/classes/NonceGeneratorMiddleware.php(22): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#35 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Zaxbux\SecurityHeaders\Classes\NonceGeneratorMiddleware->handle()
#36 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(116): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#37 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(165): Illuminate\Pipeline\Pipeline->then()
#38 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(134): Illuminate\Foundation\Http\Kernel->sendRequestThroughRouter()
#39 /var/www/html/index.php(70): Illuminate\Foundation\Http\Kernel->handle()
#40 {main}

It does not look like our plugin is the cause of this error. The reason it shows up in the stacktrace, is because it shows all the web middleware on the route. All these are web middleware:

#9 /var/www/html/plugins/vdlp/twofactorauthentication/classes/TwoFactorMiddleware.php(57): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#10 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Vdlp\TwoFactorAuthentication\Classes\TwoFactorMiddleware->handle()
#11 /var/www/html/vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php(50): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#12 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Routing\Middleware\SubstituteBindings->handle()
#13 /var/www/html/vendor/laravel/framework/src/Illuminate/View/Middleware/ShareErrorsFromSession.php(49): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#14 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\View\Middleware\ShareErrorsFromSession->handle()
#15 /var/www/html/vendor/laravel/framework/src/Illuminate/Session/Middleware/StartSession.php(121): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()
#16 /var/www/html/vendor/laravel/framework/src/Illuminate/Session/Middleware/StartSession.php(64): Illuminate\Session\Middleware\StartSession->handleStatefulRequest()
#17 /var/www/html/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(180): Illuminate\Session\Middleware\StartSession->handle()
#18 /var/www/html/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/AddQueuedCookiesToResponse.php(37): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}()

You should contact RainLab, because it most likely is an issue in their own plugin.

thanks for your reply. Indeed, I contacted RainLab few weeks ago, and they think it is this plugin which is at the origin of the problem. I am gonna disable the 2FA on the UAT server and see what comes up.