diff --git a/README.md b/README.md
index f72fc2ca53ab017cef4478ac2826a5f88beafe97..a43277737ef67c2888ad135b80dad9566a3117c5 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,6 @@ views, blocks...).
 See the [docs](./docs) folder for more detailed documentation on:
 - [details element](./docs/Details.md)
 - [form API](./docs/Forms.md)
-- [modal](./docs/Modal.md)
 - [what is out of scope](./docs/Out-of-scope.md)
 
 
diff --git a/assets/js/misc/dialog/dialog.ajax.js b/assets/js/misc/dialog/dialog.ajax.js
deleted file mode 100644
index ec16268d83ed61bba3baf80aef6438d19a78f948..0000000000000000000000000000000000000000
--- a/assets/js/misc/dialog/dialog.ajax.js
+++ /dev/null
@@ -1,240 +0,0 @@
-/**
- * @file
- * Extends the Drupal AJAX functionality to integrate the dialog API.
- */
-
-(($, Drupal) => {
-  /**
-   * Initialize dialogs for Ajax purposes.
-   *
-   * @type {Drupal~behavior}
-   *
-   * @prop {Drupal~behaviorAttach} attach
-   *   Attaches the behaviors for dialog ajax functionality.
-   */
-  Drupal.behaviors.dialog = {
-    attach: function attach(context, settings) {
-      const $context = $(context);
-
-      if (!$('#drupal-modal').length) {
-        $(
-          `<div id="drupal-modal" class="modal fade" tabindex="-1" role="dialog">
-            <div class="modal-dialog" role="document">
-              <div class="modal-content"></div>
-            </div>
-          </div>`,
-        )
-          .hide()
-          .appendTo('body');
-      }
-
-      const $dialog = $context.closest('.modal-content');
-      if ($dialog.length) {
-        const dialogSettings = $dialog.closest('.modal').data('settings');
-        if (dialogSettings && dialogSettings.drupalAutoButtons) {
-          $dialog.trigger('dialogButtonsChange');
-        }
-      }
-
-      const originalClose = settings.dialog.close;
-
-      settings.dialog.close = (event) => {
-        for (
-          // eslint-disable-next-line
-          var _len = arguments.length,
-            args = Array(_len > 1 ? _len - 1 : 0),
-            _key = 1;
-          _key < _len;
-          _key++
-        ) {
-          // eslint-disable-next-line
-          args[_key - 1] = arguments[_key];
-        }
-
-        // eslint-disable-next-line
-        originalClose.apply(settings.dialog, [event].concat(args));
-        $(event.target).remove();
-      };
-    },
-    prepareDialogButtons: function prepareDialogButtons($dialog) {
-      const buttons = [];
-      const $buttons = $dialog.find(
-        '.form-actions input[type=submit], .form-actions button[type=submit], .form-actions a.button',
-      );
-      // eslint-disable-next-line func-names
-      $buttons.each(function () {
-        const $originalButton = $(this);
-        this.style.display = 'none';
-        buttons.push({
-          text: $originalButton.html() || $originalButton.attr('value'),
-          class: $originalButton.attr('class'),
-          click: function click(e) {
-            if ($originalButton[0].tagName === 'A') {
-              $originalButton[0].click();
-            } else {
-              $originalButton
-                .trigger('mousedown')
-                .trigger('mouseup')
-                .trigger('click');
-              e.preventDefault();
-            }
-          },
-        });
-      });
-      return buttons;
-    },
-  };
-
-  // eslint-disable-next-line
-  Drupal.AjaxCommands.prototype.openDialogByUrl = (ajax, response, status) => {
-    const settings = $.extend(response.settings, {});
-
-    const elementSettings = {
-      progress: {
-        type: 'throbber',
-      },
-      dialogType: '_modal',
-      dialog: response.dialogOptions,
-      url: settings.url,
-    };
-
-    const dialogUrlAjax = Drupal.ajax(elementSettings);
-    dialogUrlAjax.execute();
-  };
-
-  Drupal.AjaxCommands.prototype.coreOpenDialog =
-    Drupal.AjaxCommands.prototype.openDialog;
-
-  Drupal.AjaxCommands.prototype.openDialog = (ajax, response, status) => {
-    if (ajax.dialogRenderer === 'off_canvas') {
-      return Drupal.AjaxCommands.prototype.coreOpenDialog(
-        ajax,
-        response,
-        status,
-      );
-    }
-
-    if (!response.selector) {
-      return false;
-    }
-    let $dialog = $(response.selector);
-    if (!$dialog.length) {
-      $dialog = $(
-        `<div id="${response.selector.replace(
-          /^#/,
-          '',
-        )}" class="modal fade" tabindex="-1" role="dialog">
-          <div class="modal-dialog" role="document">
-            <div class="modal-content"></div>
-          </div>
-        </div>`,
-      )
-        .hide()
-        .appendTo('body');
-    }
-
-    if (!ajax.wrapper) {
-      response.selector = `${response.selector.toString()} .modal-content`;
-    }
-
-    response.command = 'insert';
-    response.method = 'html';
-    response.dialogOptions = response.dialogOptions || {};
-
-    // Do some extra things here, set Drupal.autocomplete options to render
-    // autocomplete box inside the modal.
-    if (
-      Drupal.autocomplete !== undefined &&
-      Drupal.autocomplete.options !== undefined
-    ) {
-      Drupal.autocomplete.options.appendTo = response.selector;
-    }
-    if (
-      response.dialogOptions.modalDialogWrapBody === undefined ||
-      response.dialogOptions.modalDialogWrapBody === true ||
-      response.dialogOptions.modalDialogWrapBody === 'true'
-    ) {
-      response.data = `<div class="modal-body">${response.data}</div>`;
-    }
-    ajax.commands.insert(ajax, response, status);
-
-    // Move the buttons to the Bootstrap dialog buttons area.
-    if (typeof response.dialogOptions.drupalAutoButtons === 'undefined') {
-      response.dialogOptions.drupalAutoButtons = true;
-    } else if (response.dialogOptions.drupalAutoButtons === 'false') {
-      response.dialogOptions.drupalAutoButtons = false;
-    } else {
-      response.dialogOptions.drupalAutoButtons =
-        !!response.dialogOptions.drupalAutoButtons;
-    }
-    if (
-      !response.dialogOptions.buttons &&
-      response.dialogOptions.drupalAutoButtons
-    ) {
-      response.dialogOptions.buttons =
-        Drupal.behaviors.dialog.prepareDialogButtons($dialog);
-    }
-
-    // Bind dialogButtonsChange.
-    $dialog.on('dialogButtonsChange', () => {
-      const buttons = Drupal.behaviors.dialog.prepareDialogButtons($dialog);
-      const dialog = Drupal.uiSuiteDialog($dialog.get(0));
-      dialog.updateButtons(buttons);
-    });
-
-    // Open the dialog itself.
-    response.dialogOptions = response.dialogOptions || {};
-    const dialog = Drupal.uiSuiteDialog($dialog.get(0), response.dialogOptions);
-    if (response.dialogOptions.modal) {
-      dialog.showModal();
-    } else {
-      dialog.show();
-    }
-
-    // Add the standard Drupal class for buttons for style consistency.
-    $dialog.parent().find('.ui-dialog-buttonset').addClass('form-actions');
-  };
-
-  // eslint-disable-next-line
-  Drupal.AjaxCommands.prototype.closeDialog = (ajax, response, status) => {
-    const $dialog = $(response.selector);
-    if ($dialog.length) {
-      Drupal.uiSuiteDialog($dialog.get(0)).close();
-    }
-
-    $dialog.off('dialogButtonsChange');
-  };
-
-  // eslint-disable-next-line
-  Drupal.AjaxCommands.prototype.setDialogOption = (ajax, response, status) => {
-    const $dialog = $(response.selector);
-    if ($dialog.length) {
-      $dialog.dialog('option', response.optionName, response.optionValue);
-    }
-  };
-
-  // eslint-disable-next-line
-  $(window).on("dialog:aftercreate", (e, dialog, $element, settings) => {
-    // eslint-disable-next-line
-    $element.on("click.dialog", ".dialog-cancel", (e) => {
-      dialog.close('cancel');
-      e.preventDefault();
-      e.stopPropagation();
-    });
-  });
-
-  $(window).on('dialog:beforeclose', (e, dialog, $element) => {
-    $element.off('.dialog');
-
-    // Do some extra things here, set Drupal.autocomplete options to render
-    // autocomplete box inside the modal.
-    if (
-      Drupal.autocomplete !== undefined &&
-      Drupal.autocomplete.options !== undefined
-    ) {
-      if (Drupal.autocomplete.options.appendTo !== undefined) {
-        delete Drupal.autocomplete.options.appendTo;
-      }
-    }
-  });
-})(jQuery, Drupal);
diff --git a/assets/js/misc/dialog/dialog.js b/assets/js/misc/dialog/dialog.js
deleted file mode 100644
index ca7e6c00d7ea40e11cfb1d379cdb6a33f780c477..0000000000000000000000000000000000000000
--- a/assets/js/misc/dialog/dialog.js
+++ /dev/null
@@ -1,226 +0,0 @@
-/**
- * @file
- * Dialog API inspired by HTML5 dialog element.
- *
- * @see http://www.whatwg.org/specs/web-apps/current-work/multipage/commands.html#the-dialog-element
- */
-
-(($, Drupal, drupalSettings) => {
-  /**
-   * Default dialog options.
-   *
-   * @type {object}
-   *
-   * @prop {bool} [autoOpen=true]
-   * @prop {bool} [backdrop=undefined]
-   * @prop {string} [buttonClass='btn']
-   * @prop {string} [buttonPrimaryClass='btn-primary']
-   * @prop {function} close
-   * @prop {string} [dialogClasses='']
-   * @prop {string} [dialogHeadingLevel=5]
-   * @prop {string} [dialogShowHeader=true]
-   * @prop {string} [dialogShowHeaderTitle=true]
-   * @prop {string} [dialogStatic=false]
-   * @prop {bool} [drupalAutoButtons=undefined]
-   * @prop {string} [title=undefined]
-   * @prop {string} [width=undefined]
-   */
-  drupalSettings.dialog = {
-    autoOpen: true,
-    backdrop: undefined,
-    buttonClass: 'btn',
-    buttonPrimaryClass: 'btn-primary',
-    close: function close(event) {
-      Drupal.uiSuiteDialog(event.target).close();
-      Drupal.detachBehaviors(event.target, null, 'unload');
-    },
-    dialogClasses: '',
-    dialogHeadingLevel: 5,
-    dialogShowHeader: true,
-    dialogShowHeaderTitle: true,
-    dialogStatic: false,
-    drupalAutoButtons: undefined,
-    title: undefined,
-    width: undefined,
-  };
-
-  /**
-   * @typedef {object} Drupal.dialog~dialogDefinition
-   *
-   * @prop {boolean} open
-   *   Is the dialog open or not.
-   * @prop {*} returnValue
-   *   Return value of the dialog.
-   * @prop {function} show
-   *   Method to display the dialog on the page.
-   * @prop {function} showModal
-   *   Method to display the dialog as a modal on the page.
-   * @prop {function} close
-   *   Method to hide the dialog from the page.
-   */
-
-  /**
-   * Polyfill HTML5 dialog element with jQueryUI.
-   *
-   * @param {HTMLElement} element
-   *   The element that holds the dialog.
-   * @param {object} options
-   *   jQuery UI options to be passed to the dialog.
-   *
-   * @return {Drupal.dialog~dialogDefinition}
-   *   The dialog instance.
-   */
-  Drupal.uiSuiteDialog = (element, options) => {
-    let undef;
-
-    const $element = $(element);
-    const domElement = $element.get(0);
-
-    const dialog = {
-      open: false,
-      returnValue: undef,
-    };
-
-    options = $.extend({}, drupalSettings.dialog, options);
-
-    function settingIsTrue(setting) {
-      return setting !== undefined && (setting === true || setting === 'true');
-    }
-
-    function updateButtons(buttons) {
-      const modalFooter = $('<div class="modal-footer">');
-      // eslint-disable-next-line func-names
-      $.each(buttons, function () {
-        const buttonObject = this;
-        const classes = [options.buttonClass, options.buttonPrimaryClass];
-
-        const button = $('<button type="button">');
-        if (buttonObject.attributes !== undefined) {
-          $(button).attr(buttonObject.attributes);
-        }
-        $(button)
-          .addClass(buttonObject.class)
-          .click((e) => {
-            if (buttonObject.click !== undefined) {
-              buttonObject.click(e);
-            }
-          })
-          .html(buttonObject.text);
-
-        if (
-          $(button).attr('class') &&
-          !$(button)
-            .attr('class')
-            .match(/\bbtn-.*/)
-        ) {
-          $(button).addClass(classes.join(' '));
-        }
-
-        $(modalFooter).append(button);
-      });
-      if (
-        $('.modal-dialog .modal-content .modal-footer', $element).length > 0
-      ) {
-        $('.modal-dialog .modal-content .modal-footer', $element).remove();
-      }
-      if ($(modalFooter).html().length > 0) {
-        $(modalFooter).appendTo($('.modal-dialog .modal-content', $element));
-      }
-    }
-
-    function openDialog(settings) {
-      settings = $.extend({}, options, settings);
-
-      // eslint-disable-next-line no-undef
-      const event = new DrupalDialogEvent('beforecreate', dialog, settings);
-      domElement.dispatchEvent(event);
-      dialog.open = true;
-      settings = event.settings;
-
-      if (settings.dialogClasses !== undefined) {
-        $('.modal-dialog', $element)
-          .removeAttr('class')
-          .addClass('modal-dialog')
-          .addClass(settings.dialogClasses);
-      }
-
-      // The modal dialog header.
-      if (settingIsTrue(settings.dialogShowHeader)) {
-        let modalHeader = '<div class="modal-header">';
-        const heading = settings.dialogHeadingLevel;
-
-        if (settingIsTrue(settings.dialogShowHeaderTitle)) {
-          modalHeader += `<h${heading} class="modal-title">${settings.title}</h${heading}>`;
-        }
-
-        // @todo use the pattern button_close directly if possible in JS.
-        modalHeader += `<button type="button" class="close btn-close" data-bs-dismiss="modal" data-dismiss="modal" aria-label="${Drupal.t(
-          'Close',
-        )}"></button></div>`;
-
-        $(modalHeader).prependTo($('.modal-dialog .modal-content', $element));
-      }
-
-      if (settingIsTrue(settings.dialogStatic)) {
-        $element.attr('data-bs-backdrop', 'static');
-        $element.attr('data-bs-keyboard', 'false');
-      }
-
-      if (
-        settingIsTrue(settings.drupalAutoButtons) &&
-        settings.buttons.length > 0
-      ) {
-        updateButtons(settings.buttons);
-      }
-
-      if ($element.modal !== undefined) {
-        $element.modal(settings);
-        $element.modal('show');
-      }
-
-      if (settings.width) {
-        const $dialog = $('.modal-dialog', $element);
-        $dialog[0].style.maxWidth = settings.width;
-      }
-
-      domElement.dispatchEvent(
-        // eslint-disable-next-line no-undef
-        new DrupalDialogEvent('aftercreate', dialog, settings),
-      );
-    }
-
-    function closeDialog(value) {
-      if ($element.modal !== undefined) {
-        $element.modal('hide');
-      }
-      dialog.returnValue = value;
-      dialog.open = false;
-    }
-
-    dialog.updateButtons = (buttons) => {
-      updateButtons(buttons);
-    };
-
-    dialog.show = () => {
-      openDialog({ backdrop: false });
-    };
-    dialog.showModal = () => {
-      openDialog({ backdrop: true });
-    };
-    dialog.close = () => {
-      closeDialog({});
-    };
-
-    $element.on('hide.bs.modal', () => {
-      // eslint-disable-next-line no-undef
-      domElement.dispatchEvent(new DrupalDialogEvent('beforeclose', dialog));
-    });
-
-    $element.on('hidden.bs.modal', () => {
-      // eslint-disable-next-line no-undef
-      domElement.dispatchEvent(new DrupalDialogEvent('afterclose', dialog));
-    });
-
-    return dialog;
-  };
-})(jQuery, Drupal, drupalSettings);
diff --git a/docs/Modal.md b/docs/Modal.md
deleted file mode 100644
index 0ff8a5c56dd1e2268a1207c5a9c6255ab10f45fa..0000000000000000000000000000000000000000
--- a/docs/Modal.md
+++ /dev/null
@@ -1,42 +0,0 @@
-# Modal
-
-UI Suite Bootstrap replaces the Drupal core modal to provide Bootstrap's one.
-
-
-## Example
-
-Here is an example to create a modal opening link with some customized options:
-
-```php
-$modal_options = [
-  'dialogClasses' => 'modal-dialog-centered',
-  'dialogShowHeader' => 'false',
-];
-
-$build['modal_link'] = [
-  '#type' => 'link',
-  '#title' => $this->t('Link title'),
-  '#url' => Url::fromRoute('my_route'),
-  '#attributes' => [
-    'class' => ['use-ajax'],
-    'data-dialog-type' => 'modal',
-    'data-dialog-options' => Json::encode($modal_options),
-  ],
-];
-```
-
-
-## Options
-
-The list of options as well as there default value can be found in
-[dialog.js](../assets/js/misc/dialog/dialog.es6.js) (`drupalSettings.dialog`).
-
-| Option                | Type    | Default value | Description                                                                  |
-|-----------------------|---------|---------------|------------------------------------------------------------------------------|
-| dialogClasses         | string  | (empty)       |                                                                              |
-| dialogShowHeader      | boolean | true          |                                                                              |
-| dialogShowHeaderTitle | boolean | true          |                                                                              |
-| dialogStatic          | boolean | false         |                                                                              |
-| dialogHeadingLevel    | integer | 5             |                                                                              |
-| buttonClass           | string  | btn           |                                                                              |
-| buttonPrimaryClass    | string  | btn-primary   | Will only have an impact if the button does not already have a `btn-` class. |
diff --git a/ui_suite_bootstrap.info.yml b/ui_suite_bootstrap.info.yml
index 8f48682dcd1c640637fa9df3df153081f7ceda4a..99bf9f060ac8522195eea6cc36be1e699656fb2e 100644
--- a/ui_suite_bootstrap.info.yml
+++ b/ui_suite_bootstrap.info.yml
@@ -46,12 +46,6 @@ libraries-extend:
     - ui_suite_bootstrap/drupal.ajax
   core/drupal.checkbox:
     - ui_suite_bootstrap/drupal.checkbox
-  core/drupal.dialog:
-    - ui_suite_bootstrap/drupal.dialog
-  #  core/drupal.dialog:
-  #    - ui_suite_bootstrap/drupal.dialog
-  #  core/drupal.dialog.ajax:
-  #    - ui_suite_bootstrap/drupal.dialog.ajax
   core/drupal.message:
     - ui_suite_bootstrap/drupal.message
   core/drupal.progress:
diff --git a/ui_suite_bootstrap.libraries.yml b/ui_suite_bootstrap.libraries.yml
index 3d468505f203a90ae628f0a0726c83d5ba307b75..e9afe880a8c88d063e78aa1bb5b0466976d08b9f 100644
--- a/ui_suite_bootstrap.libraries.yml
+++ b/ui_suite_bootstrap.libraries.yml
@@ -35,22 +35,6 @@ drupal.checkbox:
   dependencies:
     - core/drupal
 
-drupal.dialog:
-  js:
-    assets/js/misc/dialog/dialog.js: {}
-  dependencies:
-    - core/jquery
-    - core/drupal
-    - core/drupalSettings
-
-drupal.dialog.ajax:
-  js:
-    assets/js/misc/dialog/dialog.ajax.js: {}
-  dependencies:
-    - core/jquery
-    - core/drupal
-    - core/drupal.ajax
-
 drupal.dialog.off_canvas:
   css:
     component: