social_event_max_enroll defect

Problem/Motivation

It seems, that it is not possible to set a max limit for enrollments anymore.
Module: social_event_max_enroll

Steps to reproduce

1) Create an event.
2) Set a max-limit. Save the event.
3) Reopening is not possible. See error below:

Error: Attempt to modify property "options" on null in social_event_max_enroll_views_post_render()

#0 [internal function]: social_event_max_enroll_views_post_render(Object(Drupal\views\ViewExecutable), Array, Object(Drupal\views\Plugin\views\cache\Tag))
#1 /Drupal/Core/Extension/ModuleHandler.php(409): call_user_func_array(Object(Closure), Array)
#2 /Drupal/Core/Extension/ModuleHandler.php(388): Drupal\Core\Extension\ModuleHandler->Drupal\Core\Extension\{closure}(Object(Closure), 'social_event_ma...')
#3 /Drupal/Core/Extension/ModuleHandler.php(408): Drupal\Core\Extension\ModuleHandler->invokeAllWith('views_post_rend...', Object(Closure))
#4 /.../core/modules/views/src/ViewExecutable.php(1555): Drupal\Core\Extension\ModuleHandler->invokeAll('views_post_rend...', Array)
#5 /.../core/modules/views/src/Plugin/views/display/Block.php(131): Drupal\views\ViewExecutable->render()
#6 /.../core/modules/views/src/ViewExecutable.php(1645): Drupal\views\Plugin\views\display\Block->execute()
#7 /.../core/modules/views/src/Element/View.php(81): Drupal\views\ViewExecutable->executeDisplay('event_enrollmen...', Array)
#8 /.../core/modules/views/src/Plugin/Block/ViewsBlock.php(61): Drupal\views\Element\View::preRenderViewElement(Array)
#9 /.../core/modules/block/src/BlockViewBuilder.php(171): Drupal\views\Plugin\Block\ViewsBlock->build()
#10 [internal function]: Drupal\block\BlockViewBuilder::preRender(Array)
#11 /.../core/lib/Drupal/Core/Security/DoTrustedCallbackTrait.php(111): call_user_func_array('Drupal\\block\\Bl...', Array)
#12 /.../core/lib/Drupal/Core/Render/Renderer.php(859): Drupal\Core\Render\Renderer->doTrustedCallback('Drupal\\block\\Bl...', Array, 'Render #pre_ren...', 'exception', 'Drupal\\Core\\Ren...')
#13 /.../core/lib/Drupal/Core/Render/Renderer.php(421): Drupal\Core\Render\Renderer->doCallback('#pre_render', 'Drupal\\block\\Bl...', Array)
#14 /.../core/lib/Drupal/Core/Render/Renderer.php(493): Drupal\Core\Render\Renderer->doRender(Array)
#15 /.../core/lib/Drupal/Core/Render/Renderer.php(240): Drupal\Core\Render\Renderer->doRender(Array, false)
#16 /.../core/lib/Drupal/Core/Template/TwigExtension.php(475): Drupal\Core\Render\Renderer->render(Array)
#17 /.../sites/default/files/php/twig/...--sky.html.twig_.../_....php(167): Drupal\Core\Template\TwigExtension->escapeFilter(Object(Drupal\Core\Template\TwigEnvironment), Array, 'html', NULL, true)
#18 /.../vendor/twig/twig/src/Template.php(171): __TwigTemplate_f54728d603a6c30b430d802f042e7082->block_section(Array, Array)
#19 /.../sites/default/files/php/twig/6605c5cc0ce99_page--sky.html.twig_mCVy702YXq8rmkKWYueHm_P8F/_9wHEqf625fzpUhPEg-YkRlqAhpMbFuERgDsxsqnZJ8.php(96): Twig\Template->displayBlock('section', Array, Array)
#20 /.../vendor/twig/twig/src/Template.php(394): __TwigTemplate_f54728d603a6c30b430d802f042e7082->doDisplay(Array, Array)
#21 /.../vendor/twig/twig/src/Template.php(367): Twig\Template->displayWithErrorHandling(Array, Array)
#22 /.../vendor/twig/twig/src/Template.php(379): Twig\Template->display(Array)
#23 /.../vendor/twig/twig/src/TemplateWrapper.php(38): Twig\Template->render(Array)
#24 /.../core/themes/engines/twig/twig.engine(39): Twig\TemplateWrapper->render(Array)
#25 /.../core/lib/Drupal/Core/Theme/ThemeManager.php(348): twig_render_template('themes/contrib/...', Array)
#26 /.../core/lib/Drupal/Core/Render/Renderer.php(480): Drupal\Core\Theme\ThemeManager->render('page', Array)
#27 /.../core/lib/Drupal/Core/Render/Renderer.php(240): Drupal\Core\Render\Renderer->doRender(Array, false)
#28 /.../core/lib/Drupal/Core/Template/TwigExtension.php(475): Drupal\Core\Render\Renderer->render(Array)
#29 /.../sites/default/files/php/twig/6605c5cc0ce99_html.html.twig_....php(106): Drupal\Core\Template\TwigExtension->escapeFilter(Object(Drupal\Core\Template\TwigEnvironment), Array, 'html', NULL, true)
#30 /.../vendor/twig/twig/src/Template.php(394): __TwigTemplate_4ba4171a3748177474345da73bb5023a->doDisplay(Array, Array)
#31 /.../vendor/twig/twig/src/Template.php(367): Twig\Template->displayWithErrorHandling(Array, Array)
#32 /.../vendor/twig/twig/src/Template.php(379): Twig\Template->display(Array)
#33 /.../vendor/twig/twig/src/TemplateWrapper.php(38): Twig\Template->render(Array)
#34 /.../core/themes/engines/twig/twig.engine(39): Twig\TemplateWrapper->render(Array)
#35 /.../core/lib/Drupal/Core/Theme/ThemeManager.php(348): twig_render_template('themes/contrib/...', Array)
#36 /.../core/lib/Drupal/Core/Render/Renderer.php(480): Drupal\Core\Theme\ThemeManager->render('html', Array)
#37 /.../core/lib/Drupal/Core/Render/Renderer.php(240): Drupal\Core\Render\Renderer->doRender(Array, false)
#38 /.../core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(158): Drupal\Core\Render\Renderer->render(Array)
#39 /.../core/lib/Drupal/Core/Render/Renderer.php(627): Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}()
#40 /.../core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php(153): Drupal\Core\Render\Renderer->executeInRenderContext(Object(Drupal\Core\Render\RenderContext), Object(Closure))
#41 /.../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))
#42 [internal function]: Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object(Symfony\Component\HttpKernel\Event\ViewEvent), 'kernel.view', Object(Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher))
#43 /.../core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php(111): call_user_func(Array, Object(Symfony\Component\HttpKernel\Event\ViewEvent), 'kernel.view', Object(Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher))
#44 /.../vendor/symfony/http-kernel/HttpKernel.php(186): Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object(Symfony\Component\HttpKernel\Event\ViewEvent), 'kernel.view')
#45 /.../vendor/symfony/http-kernel/HttpKernel.php(76): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1)
#46 /.../core/lib/Drupal/Core/StackMiddleware/Session.php(58): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#47 /.../core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#48 /.../core/lib/Drupal/Core/StackMiddleware/ContentLength.php(28): Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#49 /.../core/modules/page_cache/src/StackMiddleware/PageCache.php(106): Drupal\Core\StackMiddleware\ContentLength->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#50 /.../core/modules/page_cache/src/StackMiddleware/PageCache.php(85): Drupal\page_cache\StackMiddleware\PageCache->pass(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#51 /.../modules/cleantalk/src/EventSubscriber/BootSubscriber.php(209): Drupal\page_cache\StackMiddleware\PageCache->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#52 /.../core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\...\EventSubscriber\BootSubscriber->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#53 /.../core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#54 /.../core/lib/Drupal/Core/StackMiddleware/AjaxPageState.php(36): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#55 /.../core/lib/Drupal/Core/StackMiddleware/StackedHttpKernel.php(51): Drupal\Core\StackMiddleware\AjaxPageState->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#56 /.../core/lib/Drupal/Core/DrupalKernel.php(704): Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#57 /.../index.php(19): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request))
#58 {main}