diff -u b/core/modules/language/language.module b/core/modules/language/language.module
--- b/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -111,6 +111,22 @@
 }
 
 /**
+ * Returns a list of supported entity types.
+ *
+ * @return array
+ *   An array of entity type names.
+ */
+function language_entity_supported() {
+  $supported = array();
+  foreach (\Drupal::entityManager()->getDefinitions() as $entity_type_id => $entity_type) {
+    if ($entity_type->isTranslatable()) {
+      $supported[$entity_type_id] = $entity_type_id;
+    }
+  }
+  return $supported;
+}
+
+/**
  * Implements hook_element_info_alter().
  */
 function language_element_info_alter(&$type) {
@@ -140,22 +156,6 @@
 }
 
 /**
- * Returns a list of supported entity types.
- *
- * @return array
- *   An array of entity type names.
- */
-function language_entity_supported() {
-  $supported = array();
-  foreach (\Drupal::entityManager()->getDefinitions() as $entity_type_id => $entity_type) {
-    if ($entity_type->isTranslatable()) {
-      $supported[$entity_type_id] = $entity_type_id;
-    }
-  }
-  return $supported;
-}
-
-/**
  * Implements hook_element_info_alter().
  */
 function language_element_info_alter(&$type) {
@@ -238,7 +238,7 @@
 
   // Do not add the submit callback for the language content settings page,
   // which is handled separately.
-  if ($form['#form_id'] != 'language_content_settings_form') {
+  if (array_search('language_content_settings_form_submit', $form['#submit']) === FALSE) {
     // Determine where to attach the language_configuration element submit handler.
     // @todo Form API: Allow form widgets/sections to declare #submit handlers.
     if (isset($form['actions']['submit']['#submit']) && array_search('language_configuration_element_submit', $form['actions']['submit']['#submit']) === FALSE) {
@@ -283,7 +283,7 @@
 
   // Do not add the submit callback for the language content settings page,
   // which is handled separately.
-  if (array_search('language_content_settings_form_submit', $form['#submit']) === FALSE) {
+  if ($form['#form_id'] != 'language_content_settings_form') {
     // Determine where to attach the language_configuration element submit handler.
     // @todo Form API: Allow form widgets/sections to declare #submit handlers.
     if (isset($form['actions']['submit']['#submit']) && array_search('language_configuration_element_submit', $form['actions']['submit']['#submit']) === FALSE) {