diff --git a/config/schema/menu_block.schema.yml b/config/schema/menu_block.schema.yml
old mode 100644
new mode 100755
index ad08127..895f0ee
--- a/config/schema/menu_block.schema.yml
+++ b/config/schema/menu_block.schema.yml
@@ -17,3 +17,7 @@ block.settings.menu_block:*:
     suggestion:
       type: string
       label: 'Theme suggestion'
+    module_additions:
+      type: config_object
+      label: 'Module Additions'
+      
\ No newline at end of file
diff --git a/src/Plugin/Block/MenuBlock.php b/src/Plugin/Block/MenuBlock.php
old mode 100644
new mode 100755
index fab522a..9c4ff48
--- a/src/Plugin/Block/MenuBlock.php
+++ b/src/Plugin/Block/MenuBlock.php
@@ -72,6 +72,8 @@ class MenuBlock extends SystemMenuBlock {
       ],
     ];
 
+    \Drupal::moduleHandler()->alter('menu_block_build_form', $form, $this->configuration['module_additions']);
+
     // Open the details field sets if their config is not set to defaults.
     foreach(['menu_levels', 'advanced', 'style'] as $fieldSet) {
       foreach (array_keys($form[$fieldSet]) as $field) {
@@ -103,6 +105,7 @@ class MenuBlock extends SystemMenuBlock {
     $this->configuration['expand'] = $form_state->getValue('expand');
     $this->configuration['parent'] = $form_state->getValue('parent');
     $this->configuration['suggestion'] = $form_state->getValue('suggestion');
+    $this->configuration['module_additions'] = $form_state->getValue('module_additions');
   }
 
   /**
@@ -164,6 +167,8 @@ class MenuBlock extends SystemMenuBlock {
     $tree = $this->menuTree->transform($tree, $manipulators);
     $build = $this->menuTree->build($tree);
 
+    \Drupal::moduleHandler()->alter('menu_block_build', $build, $this->configuration['module_additions']);
+
     if (!empty($build['#theme'])) {
       // Add the configuration for use in menu_block_theme_suggestions_menu().
       $build['#menu_block_configuration'] = $this->configuration;