several other tweaks

book/forms.rst

@@ -127,9 +127,10 @@ which HTML form tag(s) is rendered for that field.
 
 .. versionadded:: 2.8
     To denote the form type, you have to use the fully qualified class name - like
-    TextType::class in PHP 5.5+ or ``Symfony\Component\Form\Extension\Core\Type\TextType``.
+    ``TextType::class`` in PHP 5.5+ or ``Symfony\Component\Form\Extension\Core\Type\TextType``.
     Before Symfony 2.8, you could use an alias for each type like ``text`` or
-    ``date``. For more details, see the `2.8 UPGRADE Log`_.
+    ``date``. The old alias syntax will still work until Symfony 3.0. For more details,
+    see the `2.8 UPGRADE Log`_.
 
 Finally, you added a submit button with a custom label for submitting the form to
 the server.

cookbook/form/create_form_type_extension.rst

@@ -113,7 +113,7 @@ tag:
         <service id="app.image_type_extension"
             class="AppBundle\Form\Extension\ImageTypeExtension"
         >
-            <tag name="form.type_extension" extended_type="Symfony\Component\Form\Extension\Core\Type\FileType" />
+            <tag name="form.type_extension" extended-type="Symfony\Component\Form\Extension\Core\Type\FileType" />
         </service>
 
     .. code-block:: php

reference/forms/types.rst

@@ -65,3 +65,5 @@ Supported Field Types
 The following field types are natively available in Symfony:
 
 .. include:: /reference/forms/types/map.rst.inc
+
+.. _`2.8 UPGRADE Log`: https://github.com/symfony/symfony/blob/2.8/UPGRADE-2.8.md#form