1,20d0
< diff --git a/core/modules/taxonomy/config/schema/taxonomy.views.schema.yml b/core/modules/taxonomy/config/schema/taxonomy.views.schema.yml
< index 9ec9758185..98be95b22d 100644
< --- a/core/modules/taxonomy/config/schema/taxonomy.views.schema.yml
< +++ b/core/modules/taxonomy/config/schema/taxonomy.views.schema.yml
< @@ -120,9 +120,12 @@ views.filter.taxonomy_index_tid:
<    type: views.filter.many_to_one
<    label: 'Taxonomy term ID'
<    mapping:
< -    vid:
< -      type: string
< -      label: 'Vocabulary'
< +    vids:
< +      type: sequence
< +      label: 'Vocabularies'
< +      sequence:
< +        type: string
< +        label: 'Vocabulary'
<      type:
<        type: string
<        label: 'Selection type'
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< index efadf83126..baf3c68f15 100644
---
> index efadf83126..42685c79f3 100644
71c51
< +        $this->options['vids'] = [$first_vocabulary->id()];
---
> +        $this->options['vids'] = $first_vocabulary->id();
128,129c108
< -      $terms = $this->value ? Term::loadMultiple(($this->value)) : [];
< +      $terms = $this->value ? Term::loadMultiple($this->value) : [];
---
>        $terms = $this->value ? Term::loadMultiple(($this->value)) : [];
171c150
< @@ -195,16 +223,22 @@ protected function valueForm(&$form, FormStateInterface $form_state) {
---
> @@ -195,12 +223,18 @@ protected function valueForm(&$form, FormStateInterface $form_state) {
193,197d171
< -      $default_value = (array) $this->value;
< +      $default_value = $this->value;
<  
<        if ($exposed = $form_state->get('exposed')) {
<          $identifier = $this->options['expose']['identifier'];
310c284
< index 8b1b822e3e..ab3879f30b 100644
---
> index 8b1b822e3e..edf0c03ab8 100644
339c313
< @@ -46,13 +55,38 @@ class TaxonomyIndexTidUiTest extends UITestBase {
---
> @@ -46,13 +55,30 @@ class TaxonomyIndexTidUiTest extends UITestBase {
370,377d343
< +
< +    $vocab = Vocabulary::load($vocab_id);
< +    if (!$vocab) {
< +      Vocabulary::create([
< +        'vid' => $vocab_id,
< +        'name' => 'Test Vocabulary ' . $vocab_id,
< +      ])->save();
< +    }
381c347
< @@ -61,29 +95,26 @@ protected function setUp($import_test_views = TRUE) {
---
> @@ -61,22 +87,18 @@ protected function setUp($import_test_views = TRUE) {
408,417c374
<     * Tests the filter UI.
<     */
<    public function testFilterUI() {
< -    $this->drupalGet('admin/structure/views/nojs/handler/test_filter_taxonomy_index_tid/default/filter/tid');
< +    $out = $this->drupalGet('admin/structure/views/nojs/handler/test_filter_taxonomy_index_tid/default/filter/tid');
< +    $this->assertFieldByXpath('//select[@id="edit-options-value"]', NULL);
<  
<      $result = $this->xpath('//select[@id="edit-options-value"]/option');
<  
< @@ -126,6 +157,75 @@ public function testFilterUI() {
---
> @@ -126,6 +148,75 @@ public function testFilterUI() {
493,519c450,567
< @@ -203,7 +303,11 @@ public function testExposedFilter() {
<      ];
<      $this->drupalPostForm('admin/structure/views/nojs/add-handler/test_taxonomy_term_name/default/filter', $edit, 'Add and configure filter criteria');
<      // Select 'Empty Vocabulary' and 'Autocomplete' from the list of options.
< -    $this->drupalPostForm('admin/structure/views/nojs/handler-extra/test_taxonomy_term_name/default/filter/tid', [], 'Apply and continue');
< +    $edit = [
< +      'options[vids][empty_vocabulary]' => TRUE,
< +      'options[type]' => 'textfield',
< +    ];
< +    $this->drupalPostForm('admin/structure/views/nojs/handler-extra/test_taxonomy_term_name/default/filter/tid', $edit, 'Apply and continue');
<      // Expose the filter.
<      $edit = ['options[expose_button][checkbox][checkbox]' => TRUE];
<      $this->drupalPostForm('admin/structure/views/nojs/handler/test_taxonomy_term_name/default/filter/tid', $edit, 'Expose filter');
< diff --git a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_exposed_form_checkboxes.yml b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_exposed_form_checkboxes.yml
< index 26b1d3259e..f855181fd5 100644
< --- a/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_exposed_form_checkboxes.yml
< +++ b/core/modules/views/tests/modules/views_test_config/test_views/views.view.test_exposed_form_checkboxes.yml
< @@ -108,7 +108,8 @@ display:
<            reduce_duplicates: false
<            type: select
<            limit: true
< -          vid: test_exposed_checkboxes
< +          vids: 
< +            - test_exposed_checkboxes
<            hierarchy: false
<            error_message: true
<            plugin_id: taxonomy_index_tid
---
> diff --git a/core/modules/views/views.module b/core/modules/views/views.module
> index b82f36d4a5..09a5bc594f 100644
> --- a/core/modules/views/views.module
> +++ b/core/modules/views/views.module
> @@ -29,7 +29,9 @@ function views_help($route_name, RouteMatchInterface $route_match) {
>        $output .= '<h3>' . t('About') . '</h3>';
>        $output .= '<p>' . t('The Views module provides a back end to fetch information from content, user accounts, taxonomy terms, and other entities from the database and present it to the user as a grid, HTML list, table, unformatted list, etc. The resulting displays are known generally as <em>views</em>.') . '</p>';
>        $output .= '<p>' . t('For more information, see the <a href=":views">online documentation for the Views module</a>.', [':views' => 'https://www.drupal.org/documentation/modules/views']) . '</p>';
> -      $output .= '<p>' . t('In order to create and modify your own views using the administration and configuration user interface, you will need to enable either the Views UI module in core or a contributed module that provides a user interface for Views. See the <a href=":views-ui">Views UI module help page</a> for more information.', [':views-ui' => (\Drupal::moduleHandler()->moduleExists('views_ui')) ? \Drupal::url('help.page', ['name' => 'views_ui']) : '#']) . '</p>';
> +      $output .= '<p>' . t('In order to create and modify your own views using the administration and configuration user interface, you will need to enable either the Views UI module in core or a contributed module that provides a user interface for Views. See the <a href=":views-ui">Views UI module help page</a> for more information.', [
> +          ':views-ui' => (\Drupal::moduleHandler()->moduleExists('views_ui')) ? \Drupal::url('help.page', ['name' => 'views_ui']) : '#'
> +        ]) . '</p>';
>        $output .= '<h3>' . t('Uses') . '</h3>';
>        $output .= '<dl>';
>        $output .= '<dt>' . t('Adding functionality to administrative pages') . '</dt>';
> @@ -91,7 +93,12 @@ function views_theme($existing, $type, $theme, $path) {
>  
>    // Our extra version of pager from pager.inc
>    $hooks['views_mini_pager'] = $base + [
> -    'variables' => ['tags' => [], 'quantity' => 9, 'element' => 0, 'parameters' => []],
> +    'variables' => [
> +      'tags' => [],
> +      'quantity' => 9,
> +      'element' => 0,
> +      'parameters' => [],
> +    ],
>    ];
>  
>    $variables = [
> @@ -113,8 +120,18 @@ function views_theme($existing, $type, $theme, $path) {
>        'attachment_before' => [],
>        'attachment_after' => [],
>      ],
> -    'style' => ['view' => NULL, 'options' => NULL, 'rows' => NULL, 'title' => NULL],
> -    'row' => ['view' => NULL, 'options' => NULL, 'row' => NULL, 'field_alias' => NULL],
> +    'style' => [
> +      'view' => NULL,
> +      'options' => NULL,
> +      'rows' => NULL,
> +      'title' => NULL,
> +    ],
> +    'row' => [
> +      'view' => NULL,
> +      'options' => NULL,
> +      'row' => NULL,
> +      'field_alias' => NULL,
> +    ],
>      'exposed_form' => ['view' => NULL, 'options' => NULL],
>      'pager' => [
>        'view' => NULL,
> @@ -131,7 +148,13 @@ function views_theme($existing, $type, $theme, $path) {
>      'variables' => ['view' => NULL, 'field' => NULL, 'row' => NULL],
>    ];
>    $hooks['views_view_grouping'] = $base + [
> -    'variables' => ['view' => NULL, 'grouping' => NULL, 'grouping_level' => NULL, 'rows' => NULL, 'title' => NULL],
> +    'variables' => [
> +      'view' => NULL,
> +      'grouping' => NULL,
> +      'grouping_level' => NULL,
> +      'rows' => NULL,
> +      'title' => NULL,
> +    ],
>    ];
>  
>    // Only display, pager, row, and style plugins can provide theme hooks.
> @@ -241,9 +264,10 @@ function views_preprocess_node(&$variables) {
>      // If a node is being rendered in a view, and the view does not have a path,
>      // prevent drupal from accidentally setting the $page variable:
>      if (!empty($variables['view']->current_display)
> -        && $variables['page']
> -        && $variables['view_mode'] == 'full'
> -        && !$variables['view']->display_handler->hasPath()) {
> +      && $variables['page']
> +      && $variables['view_mode'] == 'full'
> +      && !$variables['view']->display_handler->hasPath()
> +    ) {
>        $variables['page'] = FALSE;
>      }
>    }
> @@ -872,6 +896,23 @@ function views_view_presave(ViewEntityInterface $view) {
>    $displays = $view->get('display');
>    $changed = FALSE;
>    foreach ($displays as $display_name => &$display) {
> +    if (isset($display['display_options']['filters'])) {
> +      foreach ($display['display_options']['filters'] as $filter_name => $filter) {
> +        if (isset($filter['plugin_id']) && $filter['plugin_id'] === 'boolean') {
> +          $new_value = FALSE;
> +          // Update all boolean and integer values to strings.
> +          if ($filter['value'] === TRUE || $filter['value'] === 1) {
> +            $new_value = '1';
> +          }
> +          elseif ($filter['value'] === FALSE || $filter['value'] === 0) {
> +            $new_value = '0';
> +          }
> +          if ($new_value !== FALSE) {
> +            $view->set("display.$display_name.display_options.filters.$filter_name.value", $new_value);
> +          }
> +        }
> +      }
> +    }
>      if (isset($display['display_options']['fields'])) {
>        foreach ($display['display_options']['fields'] as $field_name => &$field) {
>          if (isset($field['plugin_id']) && $field['plugin_id'] === 'entity_link') {
> diff --git a/core/modules/views_ui/src/Form/Ajax/ConfigHandlerExtra.php b/core/modules/views_ui/src/Form/Ajax/ConfigHandlerExtra.php
> index 8e71123389..ff7f53ce6b 100644
> --- a/core/modules/views_ui/src/Form/Ajax/ConfigHandlerExtra.php
> +++ b/core/modules/views_ui/src/Form/Ajax/ConfigHandlerExtra.php
> @@ -95,6 +95,10 @@ public function buildForm(array $form, FormStateInterface $form_state) {
>     */
>    public function validateForm(array &$form, FormStateInterface $form_state) {
>      $form_state->get('handler')->validateExtraOptionsForm($form['options'], $form_state);
> +
> +    if ($form_state->getErrors()) {
> +      $form_state->set('rerender', TRUE);
> +    }
>    }
>  
>    /**