PHP Notice: Undefined index: group

I'm having a lot of PHP notices regarding undefined index: "group" using version 1.x-dev

PHP Notice:  Undefined index: group in /www/web/modules/contrib/draggableviews/draggableviews.module on line 56
PHP Stack trace:
PHP   1. {main}() /www/vendor/drupal/console/bin/drupal:0
PHP   2. require() /www/vendor/drupal/console/bin/drupal:4
PHP   3. Drupal\Console\Application->run() /www/vendor/drupal/console/bin/drupal.php:89
PHP   4. Drupal\Console\Application->doRun() /www/vendor/symfony/console/Application.php:148
PHP   5. Drupal\Console\Application->doRun() /www/vendor/drupal/console/src/Application.php:64
PHP   6. Drupal\Console\Application->doRun() /www/vendor/drupal/console-core/src/Application.php:185
PHP   7. Drupal\Console\Application->doRunCommand() /www/vendor/symfony/console/Application.php:248
PHP   8. Drupal\Console\Command\Cache\RebuildCommand->run() /www/vendor/symfony/console/Application.php:964
PHP   9. Drupal\Console\Command\Cache\RebuildCommand->execute() /www/vendor/symfony/console/Command/Command.php:252
PHP  10. Drupal\Console\Utils\DrupalApi->drupal_rebuild() /www/vendor/drupal/console/src/Command/Cache/RebuildCommand.php:104
PHP  11. drupal_flush_all_caches() /www/vendor/drupal/console/src/Utils/DrupalApi.php:355
PHP  12. Drupal\Core\ProxyClass\Routing\RouteBuilder->rebuild() /www/web/core/includes/common.inc:1157
PHP  13. Drupal\Core\Routing\RouteBuilder->rebuild() /www/web/core/lib/Drupal/Core/ProxyClass/Routing/RouteBuilder.php:83
PHP  14. call_user_func:{/www/web/core/lib/Drupal/Core/Routing/RouteBuilder.php:146}() /www/web/core/lib/Drupal/Core/Routing/RouteBuilder.php:146
PHP  15. Drupal\views\EventSubscriber\RouteSubscriber->routes() /www/web/core/lib/Drupal/Core/Routing/RouteBuilder.php:146
PHP  16. Drupal\views\Plugin\views\display\Page->collectRoutes() /www/web/core/modules/views/src/EventSubscriber/RouteSubscriber.php:120
PHP  17. Drupal\views\Plugin\views\display\Page->getRoute() /www/web/core/modules/views/src/Plugin/views/display/PathPluginBase.php:220
PHP  18. Drupal\views\Plugin\views\display\Page->getRoute() /www/web/core/modules/views/src/Plugin/views/display/Page.php:91
PHP  19. Drupal\views\ViewExecutable->getTitle() /www/web/core/modules/views/src/Plugin/views/display/PathPluginBase.php:132
PHP  20. Drupal\views\ViewExecutable->initStyle() /www/web/core/modules/views/src/ViewExecutable.php:1842
PHP  21. Drupal\views\Plugin\views\display\Page->getPlugin() /www/web/core/modules/views/src/ViewExecutable.php:882
PHP  22. Drupal\views\Plugin\views\style\DefaultStyle->init() /www/web/core/modules/views/src/Plugin/views/display/DisplayPluginBase.php:820
PHP  23. Drupal\views\Plugin\views\display\Page->getPlugin() /www/web/core/modules/views/src/Plugin/views/style/StylePluginBase.php:122
PHP  24. Drupal\views\Plugin\ViewsPluginManager->createInstance() /www/web/core/modules/views/src/Plugin/views/display/DisplayPluginBase.php:817
PHP  25. Drupal\Core\Plugin\Factory\ContainerFactory->createInstance() /www/web/core/lib/Drupal/Component/Plugin/PluginManagerBase.php:84
PHP  26. Drupal\views\Plugin\ViewsPluginManager->getDefinition() /www/web/core/lib/Drupal/Core/Plugin/Factory/ContainerFactory.php:16
PHP  27. Drupal\views\Plugin\ViewsPluginManager->getDefinitions() /www/web/core/lib/Drupal/Component/Plugin/Discovery/DiscoveryCachedTrait.php:22
PHP  28. Drupal\views\Plugin\ViewsPluginManager->findDefinitions() /www/web/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php:175
PHP  29. Drupal\Core\Plugin\Discovery\ContainerDerivativeDiscoveryDecorator->getDefinitions() /www/web/core/lib/Drupal/Core/Plugin/DefaultPluginManager.php:284
PHP  30. Drupal\Core\Plugin\Discovery\ContainerDerivativeDiscoveryDecorator->getDerivatives() /www/web/core/lib/Drupal/Component/Plugin/Discovery/DerivativeDiscoveryDecorator.php:87
PHP  31. Drupal\views_parity_row\Plugin\Derivative\ViewsParityRowEntityRow->getDerivativeDefinitions() /www/web/core/lib/Drupal/Component/Plugin/Discovery/DerivativeDiscoveryDecorator.php:101
PHP  32. Drupal\views\ViewsData->get() /www/web/modules/contrib/views_parity_row/src/Plugin/Derivative/ViewsParityRowEntityRow.php:91
PHP  33. Drupal\views\ViewsData->getData() /www/web/core/modules/views/src/ViewsData.php:162
PHP  34. Drupal\Core\Extension\ModuleHandler->alter() /www/web/core/modules/views/src/ViewsData.php:254
PHP  35. draggableviews_views_data_alter() /www/web/core/lib/Drupal/Core/Extension/ModuleHandler.php:539