Undefined Variable Notice

Problem/Motivation

Receiving a undefined variable notice with the following output when going to set the settings fpr the theme:

Notice: Undefined variable: javascript in include_once() (line 143 of themes/contrib/bfd/bootstrap_for_drupal.theme).

include_once('/home/sites/sitename/public_html/themes/contrib/bfd/bootstrap_for_drupal.theme') (Line: 147)
Drupal\Core\Extension\Extension->load() (Line: 36)
twig_init(Object)
call_user_func('twig_init', Object) (Line: 146)
Drupal\Core\Theme\ThemeInitialization->loadActiveTheme(Object) (Line: 122)
Drupal\Core\Theme\ThemeManager->setActiveTheme(Object) (Line: 349)
Drupal\system\Form\ThemeSettingsForm->buildForm(Array, Object, 'bootstrap_for_drupal')
call_user_func_array(Array, Array) (Line: 532)
Drupal\Core\Form\FormBuilder->retrieveForm('system_theme_settings', Object) (Line: 278)
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: 573)
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: 158)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 80)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 57)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 47)
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: 50)
Drupal\ban\BanMiddleware->handle(Object, 1, 1) (Line: 47)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 52)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 706)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)

Steps to reproduce

Install on fresh Drupal 9.1.4

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes