diff --git a/src/Plugin/facets/widget/CheckboxWidget.php b/src/Plugin/facets/widget/CheckboxWidget.php
index d45da2e..877e478 100644
--- a/src/Plugin/facets/widget/CheckboxWidget.php
+++ b/src/Plugin/facets/widget/CheckboxWidget.php
@@ -7,14 +7,13 @@
 
 namespace Drupal\facets\Plugin\facets\widget;
 
-use Drupal\Core\Cache\CacheableRedirectResponse;
 use Drupal\Core\Form\FormInterface;
 use Drupal\Core\Form\FormStateInterface;
-use Drupal\Core\Link;
 use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Drupal\Core\Url;
 use Drupal\facets\FacetInterface;
 use Drupal\facets\Widget\WidgetInterface;
-use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
+use Symfony\Component\HttpFoundation\RedirectResponse;
 
 /**
  * The checkbox / radios widget.
@@ -30,14 +29,6 @@ class CheckboxWidget implements WidgetInterface, FormInterface {
   use StringTranslationTrait;
 
   /**
-   * The link generator.
-   *
-   * @var \Drupal\Core\Utility\LinkGeneratorInterface $linkGenerator
-   *   The link generator.
-   */
-  protected $linkGenerator;
-
-  /**
    * {@inheritdoc}
    */
   public function execute() {
@@ -87,19 +78,6 @@ class CheckboxWidget implements WidgetInterface, FormInterface {
   }
 
   /**
-   * Gets the link generator.
-   *
-   * @return \Drupal\Core\Utility\LinkGeneratorInterface
-   *   The link generator.
-   */
-  protected function linkGenerator() {
-    if (!isset($this->linkGenerator)) {
-      $this->linkGenerator = \Drupal::linkGenerator();
-    }
-    return $this->linkGenerator;
-  }
-
-  /**
    * {@inheritdoc}
    */
   public function getFormId() {
@@ -163,7 +141,9 @@ class CheckboxWidget implements WidgetInterface, FormInterface {
     /** @var \Drupal\facets\FacetInterface $facet */
     $build_info = $form_state->getBuildInfo();
     $facet = $build_info['args'][0];
+
     $result_link = FALSE;
+    $active_items = [];
 
     foreach ($values[$facet->getFieldAlias()] as $key => $value) {
       if ($value !== 0) {
@@ -178,12 +158,12 @@ class CheckboxWidget implements WidgetInterface, FormInterface {
     }
 
     // We have an active item, so redirecting to that page.
-    if ($result_link instanceof Link) {
-      return new CacheableRedirectResponse($result_link->toUriString());
+    if ($result_link instanceof Url) {
+      return new RedirectResponse($result_link->toString());
     }
 
     // Form was submitted, but nothing was selected, so we should submit to the
     // facet.
-    return new CacheableRedirectResponse('/' . $facet->getFacetSource()->getPath());
+    return new RedirectResponse('/' . $facet->getFacetSource()->getPath());
   }
 }
diff --git a/tests/src/Unit/Plugin/widget/CheckboxWidgetTest.php b/tests/src/Unit/Plugin/widget/CheckboxWidgetTest.php
index f24ee45..187dddd 100644
--- a/tests/src/Unit/Plugin/widget/CheckboxWidgetTest.php
+++ b/tests/src/Unit/Plugin/widget/CheckboxWidgetTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Tests\facets\Unit\Plugin\widget;
 
+use Drupal\Core\Form\FormState;
 use Drupal\facets\Entity\Facet;
 use Drupal\facets\Plugin\facets\widget\CheckboxWidget;
 use Drupal\facets\Result\Result;
@@ -23,7 +24,7 @@ class CheckboxWidgetTest extends UnitTestCase {
   /**
    * The processor to be tested.
    *
-   * @var \drupal\facets\Widget\WidgetInterface
+   * @var \Drupal\facets\Plugin\facets\widget\CheckboxWidget
    */
   protected $widget;
 
@@ -53,19 +54,16 @@ class CheckboxWidgetTest extends UnitTestCase {
     }
     $this->originalResults = $original_results;
 
-    $link_generator = $this->getMockBuilder('\Drupal\Core\Utility\LinkGenerator')
+    $form_builder = $this->getMockBuilder('\Drupal\Core\Form\FormBuilder')
       ->disableOriginalConstructor()
       ->getMock();
-    $link_generator->expects($this->atLeastOnce())
-      ->method('generate')
-      ->will($this->returnArgument(0));
 
     $string_translation = $this->getMockBuilder('\Drupal\Core\StringTranslation\TranslationManager')
       ->disableOriginalConstructor()
       ->getMock();
 
     $container_builder = new ContainerBuilder();
-    $container_builder->set('link_generator', $link_generator);
+    $container_builder->set('form_builder', $form_builder);
     $container_builder->set('string_translation', $string_translation);
     \Drupal::setContainer($container_builder);
 
@@ -78,34 +76,74 @@ class CheckboxWidgetTest extends UnitTestCase {
   public function testDefaultSettings() {
     $facet = new Facet([], 'facet');
     $facet->setResults($this->originalResults);
-
-    $output = $this->widget->build($facet);
-
-    $this->assertInternalType('array', $output);
-    $this->assertCount(4, $output['#items']);
-
-    $expected_links = ['Llama', 'Badger', 'Duck', 'Alpaca'];
+    $facet->setFieldIdentifier('test_field');
+
+    $formState = new FormState();
+    $formState->addBuildInfo('args', [$facet]);
+    $form = [];
+    $built_form = $this->widget->buildForm($form, $formState);
+
+    $this->assertInternalType('array', $built_form);
+    $this->assertCount(4, $built_form['test_field']['#options']);
+    $this->assertEquals('checkboxes', $built_form['test_field']['#type']);
+
+    $expected_links = [
+      'llama' => 'Llama',
+      'badger' => 'Badger',
+      'duck' => 'Duck',
+      'alpaca' => 'Alpaca'
+    ];
     foreach ($expected_links as $index => $value) {
-      $this->assertEquals($value, $output['#items'][$index]);
+      $this->assertEquals($value, $built_form['test_field']['#options'][$index]);
     }
   }
 
   /**
-   * Test widget with show numbers enabled.
+   * Test widget, make sure hiding and showing numbers works.
    */
-  public function testShowAmount() {
+  public function testHideNumbers() {
+    $original_results = $this->originalResults;
+    $original_results[1]->setActiveState(TRUE);
+
     $facet = new Facet([], 'facet');
-    $facet->setResults($this->originalResults);
+    $facet->setResults($original_results);
+    $facet->setFieldIdentifier('test__field');
+    $facet->setWidgetConfigs(['show_numbers' => 0]);
+
+    $formState = new FormState();
+    $formState->addBuildInfo('args', [$facet]);
+    $form = [];
+    $built_form = $this->widget->buildForm($form, $formState);
+
+    $this->assertInternalType('array', $built_form);
+    $this->assertCount(4, $built_form['test__field']['#options']);
+    $expected_links = [
+      'llama' => 'Llama',
+      'badger' => 'Badger',
+      'duck' => 'Duck',
+      'alpaca' => 'Alpaca'
+    ];
+    foreach ($expected_links as $index => $value) {
+      $this->assertEquals($value, $built_form['test__field']['#options'][$index]);
+    }
+
+    // Enable the 'show_numbers' setting again to make sure that the switch
+    // between those settings works.
     $facet->setWidgetConfigs(['show_numbers' => 1]);
 
-    $output = $this->widget->build($facet);
+    $built_form = $this->widget->buildForm($form, $formState);
 
-    $this->assertInternalType('array', $output);
-    $this->assertCount(4, $output['#items']);
+    $this->assertInternalType('array', $built_form);
+    $this->assertCount(4, $built_form['test__field']['#options']);
 
-    $expected_links = ['Llama (10)', 'Badger (20)', 'Duck (15)', 'Alpaca (9)'];
+    $expected_links = [
+      'llama' => 'Llama (10)',
+      'badger' => 'Badger (20)',
+      'duck' => 'Duck (15)',
+      'alpaca' => 'Alpaca (9)',
+    ];
     foreach ($expected_links as $index => $value) {
-      $this->assertEquals($value, $output['#items'][$index]);
+      $this->assertEquals($value, $built_form['test__field']['#options'][$index]);
     }
   }