diff -u b/core/includes/entity.inc b/core/includes/entity.inc
--- b/core/includes/entity.inc
+++ b/core/includes/entity.inc
@@ -149,8 +149,8 @@
  * types can specify that a different class should be used by setting the
  * "handlers['storage']" key in the entity plugin annotation. These classes
  * can either implement the Drupal\Core\Entity\EntityStorageInterface interface,
- * or, most commonly, extend the
- * Drupal\Core\Entity\Sql\SqlContentEntityStorage class.
+ * or, most commonly, extend the Drupal\Core\Entity\Sql\SqlContentEntityStorage
+ * class.
  * See Drupal\node\Entity\Node and Drupal\node\NodeStorage
  * for an example.
  *
reverted:
--- b/core/lib/Drupal/Core/Field/FieldItemInterface.php
+++ a/core/lib/Drupal/Core/Field/FieldItemInterface.php
@@ -71,8 +71,8 @@
    *   - columns: An array of Schema API column specifications, keyed by column
    *     name. The columns need to be a subset of the properties defined in
    *     propertyDefinitions(). The 'not null' property is ignored if present,
+   *     as it is determined automatically by the storage controller depending
+   *     on the table layout and the property definitions. It is recommended to
-   *     as it is determined automatically by the storage handler depending on
-   *     the table layout and the property definitions. It is recommended to
    *     avoid having the column definitions depend on field settings when
    *     possible. No assumptions should be made on how storage engines
    *     internally use the original column name to structure their storage.
diff -u b/core/modules/aggregator/src/FeedViewBuilder.php b/core/modules/aggregator/src/FeedViewBuilder.php
--- b/core/modules/aggregator/src/FeedViewBuilder.php
+++ b/core/modules/aggregator/src/FeedViewBuilder.php
@@ -16,7 +16,7 @@
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
- * View builder handler for aggregator feed items.
+ * View builder handler for aggregator feeds items.
  */
 class FeedViewBuilder extends EntityViewBuilder {
 
diff -u b/core/modules/aggregator/src/ItemViewBuilder.php b/core/modules/aggregator/src/ItemViewBuilder.php
--- b/core/modules/aggregator/src/ItemViewBuilder.php
+++ b/core/modules/aggregator/src/ItemViewBuilder.php
@@ -10,7 +10,7 @@
 use Drupal\Core\Entity\EntityViewBuilder;
 
 /**
- * View builder handler for aggregator feed items.
+ * View builder handler for aggregator feeds items.
  */
 class ItemViewBuilder extends EntityViewBuilder {
 
diff -u b/core/modules/comment/src/CommentTypeForm.php b/core/modules/comment/src/CommentTypeForm.php
--- b/core/modules/comment/src/CommentTypeForm.php
+++ b/core/modules/comment/src/CommentTypeForm.php
@@ -16,7 +16,7 @@
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
- * Base form handler for comment edit forms.
+ * Base form handler for comment type edit forms.
  */
 class CommentTypeForm extends EntityForm {
 
diff -u b/core/modules/field_ui/src/EntityDisplayModeListBuilder.php b/core/modules/field_ui/src/EntityDisplayModeListBuilder.php
--- b/core/modules/field_ui/src/EntityDisplayModeListBuilder.php
+++ b/core/modules/field_ui/src/EntityDisplayModeListBuilder.php
@@ -137,7 +137,7 @@
    *
    * @return bool
    *   TRUE if the entity has the correct view builder handler, FALSE if the
-   *   entity doesn't have the correct view builer handler.
+   *   entity doesn't have the correct view builder handler.
    */
   protected function isValidEntity($entity_type) {
     return $this->entityTypes[$entity_type]->get('field_ui_base_route') && $this->entityTypes[$entity_type]->hasViewBuilderClass();
diff -u b/core/modules/field_ui/src/EntityFormModeListBuilder.php b/core/modules/field_ui/src/EntityFormModeListBuilder.php
--- b/core/modules/field_ui/src/EntityFormModeListBuilder.php
+++ b/core/modules/field_ui/src/EntityFormModeListBuilder.php
@@ -15,7 +15,7 @@
 class EntityFormModeListBuilder extends EntityDisplayModeListBuilder {
 
   /**
-   * Filters entities based on their form handlers.
+   * Filters entities based on their form mode handlers.
    *
    * @param $entity_type
    *   The entity type of the entity that needs to be validated.