diff --git a/bootstrap.info.yml b/bootstrap.info.yml
index 153d89f..b2e6695 100644
--- a/bootstrap.info.yml
+++ b/bootstrap.info.yml
@@ -35,6 +35,8 @@ libraries-extend:
     - bootstrap/drupal.states
   core/drupal.tabledrag:
     - bootstrap/drupal.tabledrag
+  outside_in/drupal.outside_in:
+    - bootstrap/drupal.outside_in
   views/views.ajax:
     - bootstrap/views.ajax
 
diff --git a/bootstrap.libraries.yml b/bootstrap.libraries.yml
index aed147f..7337970 100644
--- a/bootstrap.libraries.yml
+++ b/bootstrap.libraries.yml
@@ -91,6 +91,13 @@ views.ajax:
   js:
     js/modules/views/ajax_view.js: {}
 
+# Create a library placeholder for outside_in module fix.
+# This is altered dynamically based on whether modals are enabled
+# @see \Drupal\bootstrap\Plugin\Alter\LibraryInfo::alter
+drupal.outside_in:
+  js:
+    js/modules/outside_in/outside_in.js: {}
+
 # libraries-override
 drupal.batch:
   js:
diff --git a/js/modules/outside_in/outside_in.js b/js/modules/outside_in/outside_in.js
new file mode 100644
index 0000000..d034baa
--- /dev/null
+++ b/js/modules/outside_in/outside_in.js
@@ -0,0 +1,170 @@
+/**
+ * @file
+ * Drupal's Settings Tray library.
+ */
+
+// We swap the Drupal.behaviors.toggleEditMode behavior because we do not want
+// the dialog to render in offcanvas when Bootstrap modals are enabled (we
+// rather prefer Bootstrap dialog over the offcanvas ones).
+// The code below is heavily copy-pasted from
+// ./core/modules/outside_in/js/outside_in.js but that's the best we can do.
+(function ($, Drupal) {
+
+  'use strict';
+
+  var blockConfigureSelector = '[data-dialog-renderer="offcanvas"]';
+  var toggleEditSelector = '[data-drupal-outsidein="toggle"]';
+  var itemsToToggleSelector = '#main-canvas, #toolbar-bar, [data-drupal-outsidein="editable"] a, [data-drupal-outsidein="editable"] button';
+  var contextualItemsSelector = '[data-contextual-id] a, [data-contextual-id] button';
+
+  /**
+   * Reacts to contextual links being added.
+   *
+   * @param {jQuery.Event} event
+   *   The `drupalContextualLinkAdded` event.
+   * @param {object} data
+   *   An object containing the data relevant to the event.
+   *
+   * @listens event:drupalContextualLinkAdded
+   */
+  $(document).on('drupalContextualLinkAdded', function (event, data) {
+    // Bind Ajax behaviors to all items showing the class.
+    // @todo Fix contextual links to work with use-ajax links in
+    //    https://www.drupal.org/node/2764931.
+    Drupal.attachBehaviors(data.$el[0]);
+
+    // Bind a listener to all 'Quick edit' links for blocks
+    // Click "Edit" button in toolbar to force Contextual Edit which starts
+    // Settings Tray edit mode also.
+    data.$el.find(blockConfigureSelector)
+      .on('click.outsidein', function () {
+        if (!isInEditMode()) {
+          $(toggleEditSelector).trigger('click.outsidein');
+        }
+      });
+  });
+
+  /**
+   * Gets all items that should be toggled with class during edit mode.
+   *
+   * @return {jQuery}
+   *   Items that should be toggled.
+   */
+  function getItemsToToggle() {
+    return $(itemsToToggleSelector).not(contextualItemsSelector);
+  }
+
+  /**
+   * Helper to check the state of the outside-in mode.
+   *
+   * @todo don't use a class for this.
+   *
+   * @return {boolean}
+   *  State of the outside-in edit mode.
+   */
+  function isInEditMode() {
+    return $('#toolbar-bar').hasClass('js-outside-in-edit-mode');
+  }
+
+  /**
+   * Helper to toggle Edit mode.
+   */
+  function toggleEditMode() {
+    setEditModeState(!isInEditMode());
+  }
+
+  /**
+   * Prevent default click events except contextual links.
+   *
+   * In edit mode the default action of click events is suppressed.
+   *
+   * @param {jQuery.Event} event
+   *   The click event.
+   */
+  function preventClick(event) {
+    // Do not prevent contextual links.
+    if ($(event.target).closest('.contextual-links').length) {
+      return;
+    }
+    event.preventDefault();
+  }
+
+  /**
+   *  Helper to switch edit mode state.
+   *
+   * @param {boolean} editMode
+   *  True enable edit mode, false disable edit mode.
+   */
+  function setEditModeState(editMode) {
+    editMode = !!editMode;
+    var $editButton = $(toggleEditSelector);
+    var $editables;
+    // Turn on edit mode.
+    if (editMode) {
+      $editButton.text(Drupal.t('Editing'));
+      // Close the Manage tray if open when entering edit mode.
+      if ($('#toolbar-item-administration-tray').hasClass('is-active')) {
+        $('#toolbar-item-administration').trigger('click');
+      }
+
+      $editables = $('[data-drupal-outsidein="editable"]').once('outsidein');
+      if ($editables.length) {
+        // Use event capture to prevent clicks on links.
+        document.querySelector('#main-canvas').addEventListener('click', preventClick, true);
+
+        // When a click occurs try and find the outside-in edit link
+        // and click it.
+        $editables
+          .not(contextualItemsSelector)
+          .on('click.outsidein', function (e) {
+            // Contextual links are allowed to function in Edit mode.
+            if ($(e.target).closest('.contextual').length || !localStorage.getItem('Drupal.contextualToolbar.isViewing')) {
+              return;
+            }
+
+            $(e.currentTarget).find(blockConfigureSelector).trigger('click');
+          });
+      }
+    }
+    // Disable edit mode.
+    else {
+      $editables = $('[data-drupal-outsidein="editable"]').removeOnce('outsidein');
+      if ($editables.length) {
+        document.querySelector('#main-canvas').removeEventListener('click', preventClick, true);
+        $editables.off('.outsidein');
+      }
+
+      $editButton.text(Drupal.t('Edit'));
+      // Close/remove offcanvas.
+      $('.ui-dialog-offcanvas .ui-dialog-titlebar-close').trigger('click');
+    }
+    getItemsToToggle().toggleClass('js-outside-in-edit-mode', editMode);
+    $('.edit-mode-inactive').toggleClass('visually-hidden', editMode);
+  }
+
+  Drupal.behaviors.toggleEditMode.attach = function () {
+
+    $(toggleEditSelector).once('outsidein').on('click.outsidein', toggleEditMode);
+
+    var search = Drupal.ajax.WRAPPER_FORMAT + '=drupal_dialog';
+    var replace = Drupal.ajax.WRAPPER_FORMAT + '=drupal_dialog_offcanvas';
+    // Loop through all Ajax links and change the format to offcanvas when
+    // needed.
+    Drupal.ajax.instances
+      .filter(function (instance) {
+        var hasElement = instance && !!instance.element;
+        var rendererOffcanvas = false;
+        var wrapperOffcanvas = false;
+        if (hasElement) {
+          rendererOffcanvas = $(instance.element).attr('data-dialog-renderer') === 'offcanvas';
+          wrapperOffcanvas = instance.options.url.indexOf('drupal_dialog_offcanvas') === -1;
+        }
+        return hasElement && rendererOffcanvas && wrapperOffcanvas;
+      })
+      .forEach(function (instance) {
+        instance.options.data.dialogOptions = {outsideInActiveEditableId: $(instance.element).parents('.outside-in-editable').attr('id')};
+        instance.progress = {type: 'fullscreen'};
+      });
+  }
+
+})(jQuery, Drupal);
diff --git a/src/Plugin/Alter/LibraryInfo.php b/src/Plugin/Alter/LibraryInfo.php
index d91f539..ecb662b 100644
--- a/src/Plugin/Alter/LibraryInfo.php
+++ b/src/Plugin/Alter/LibraryInfo.php
@@ -77,6 +77,10 @@ class LibraryInfo extends PluginBase implements AlterInterface {
           break;
         }
       }
+
+      if (!$this->theme->getSetting('modal_enabled')) {
+        unset($libraries['drupal.outside_in']['js']['js/modules/outside_in/outside_in.js']);
+      }
     }
     // Core replacements.
     elseif ($extension === 'core') {