Problem/Motivation
When I tried to create a subtheme following occuers:
Deprecated function: file_get_contents(): Passing null to parameter #2 ($use_include_path) of type bool is deprecated in Drupal\at_theme_generator\Theme\ThemeGenerator->rewritePageLayoutCSS() (line 340 of modules/contrib/at_tool/at_theme_generator/src/Theme/ThemeGenerator.php).
Drupal\at_theme_generator\Theme\ThemeGenerator->rewritePageLayoutCSS() (Line: 47)
Drupal\at_theme_generator\Theme\ThemeGeneratorTypes->starterkitGenerator() (Line: 422)
Drupal\at_theme_generator\Form\GeneratorForm->submitForm(Array, Object)
call_user_func_array(Array, Array) (Line: 114)
Drupal\Core\Form\FormSubmitter->executeSubmitHandlers(Array, Object) (Line: 52)
Drupal\Core\Form\FormSubmitter->doSubmitForm(Array, Object) (Line: 597)
Drupal\Core\Form\FormBuilder->processForm('at_generator_form', Array, Object) (Line: 325)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object) (Line: 73)
Drupal\Core\Controller\FormController->getContentResult(Object, Object)
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 583)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 166)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 74)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 704)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)