Theme suggestions form element undefined index: #type

[fsierra]

If the element doesn't have the index #type or it's empty you'll get the following error:

Notice: Undefined index: #type in lark_theme_suggestions_form_element_alter() (line 139 of /app/webroot/themes/contrib/lark/lark.theme)

#0 /app/webroot/core/includes/bootstrap.inc(600): _drupal_error_handler_real(8, 'Undefined index...', '/app/webroot/th...', 139, Array)
#1 /app/webroot/themes/contrib/lark/lark.theme(139): _drupal_error_handler(8, 'Undefined index...', '/app/webroot/th...', 139, Array)
#2 /app/webroot/core/lib/Drupal/Core/Theme/ThemeManager.php(449): lark_theme_suggestions_form_element_alter(Array, Array, 'form_element')
#3 /app/webroot/core/lib/Drupal/Core/Theme/ThemeManager.php(458): Drupal\Core\Theme\ThemeManager->alterForTheme(Object(Drupal\Core\Theme\ActiveTheme), 'theme_suggestio...', Array, Array, 'form_element')
#4 /app/webroot/core/lib/Drupal/Core/Theme/ThemeManager.php(245): Drupal\Core\Theme\ThemeManager->alter(Array, Array, Array, 'form_element')
#5 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(487): Drupal\Core\Theme\ThemeManager->render('form_element', Array)
#6 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(444): Drupal\Core\Render\Renderer->doRender(Array)
#7 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(444): Drupal\Core\Render\Renderer->doRender(Array)
#8 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(444): Drupal\Core\Render\Renderer->doRender(Array)
#9 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(444): Drupal\Core\Render\Renderer->doRender(Array)
#10 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(200): Drupal\Core\Render\Renderer->doRender(Array, false)
#11 /app/webroot/core/lib/Drupal/Core/Template/TwigExtension.php(501): Drupal\Core\Render\Renderer->render(Array)
#12 /app/vendor/twig/twig/src/Environment.php(497) : eval()'d code(55): Drupal\Core\Template\TwigExtension->escapeFilter(Object(Drupal\Core\Template\TwigEnvironment), Array, 'html', NULL, true)
#13 /app/vendor/twig/twig/src/Template.php(455): __TwigTemplate_1f227d1f12072b6d589d7609a6630a95905752f133c3c85681b0a18bacd8d189->doDisplay(Array, Array)
#14 /app/vendor/twig/twig/src/Template.php(422): Twig\Template->displayWithErrorHandling(Array, Array)
#15 /app/vendor/twig/twig/src/Template.php(434): Twig\Template->display(Array)
#16 /app/webroot/core/themes/engines/twig/twig.engine(64): Twig\Template->render(Array)
#17 /app/webroot/core/lib/Drupal/Core/Theme/ThemeManager.php(384): twig_render_template('core/modules/sy...', Array)
#18 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(431): Drupal\Core\Theme\ThemeManager->render('system_config_f...', Array)
#19 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(200): Drupal\Core\Render\Renderer->doRender(Array, false)
#20 /app/webroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(226): Drupal\Core\Render\Renderer->render(Array, false)
#21 /app/webroot/core/lib/Drupal/Core/Render/Renderer.php(573): Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}()
#22 /app/webroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(227): Drupal\Core\Render\Renderer->executeInRenderContext(Object(Drupal\Core\Render\RenderContext), Object(Closure))
#23 /app/webroot/core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(117): Drupal\Core\Render\MainContent\HtmlRenderer->prepare(Array, Object(Symfony\Component\HttpFoundation\Request), Object(Drupal\Core\Routing\CurrentRouteMatch))
#24 /app/webroot/core/lib/Drupal/Core/EventSubscriber/MainContentViewSubscriber.php(90): Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object(Symfony\Component\HttpFoundation\Request), Object(Drupal\Core\Routing\CurrentRouteMatch))
#25 [internal function]: Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object(Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent), 'kernel.view', Object(Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher))
#26 /app/webroot/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(111): call_user_func(Array, Object(Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent), 'kernel.view', Object(Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher))
#27 /app/vendor/symfony/http-kernel/HttpKernel.php(156): Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch('kernel.view', Object(Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent))
#28 /app/vendor/symfony/http-kernel/HttpKernel.php(68): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1)
#29 /app/webroot/core/lib/Drupal/Core/StackMiddleware/Session.php(57): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#30 /app/webroot/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(47): Drupal\Core\StackMiddleware\Session->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#31 /app/webroot/core/modules/page_cache/src/StackMiddleware/PageCache.php(106): Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#32 /app/webroot/core/modules/page_cache/src/StackMiddleware/PageCache.php(85): Drupal\page_cache\StackMiddleware\PageCache->pass(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#33 /app/webroot/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(47): Drupal\page_cache\StackMiddleware\PageCache->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#34 /app/webroot/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(52): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#35 /app/vendor/stack/builder/src/Stack/StackedHttpKernel.php(23): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#36 /app/webroot/core/lib/Drupal/Core/DrupalKernel.php(708): Stack\StackedHttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#37 /app/webroot/index.php(19): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request))
#38 {main}