diff --git a/src/Utility.php b/src/Utility.php
index 3637fcc..572a00a 100644
--- a/src/Utility.php
+++ b/src/Utility.php
@@ -65,10 +65,13 @@ class Utility {
    * @see https://drupal.org/node/2644502
    */
   public static function isTextType($type, array $text_types = array('text')) {
-    // @todo Currently, this is useless, but later we could also check
-    //   automatically for custom types that have one of the passed types as their
-    //   fallback.
-    return in_array($type, $text_types);
+    if (in_array($type, $text_types)) {
+      return TRUE;
+    }
+    if (in_array($type->getFallbackType(), $text_types)) {
+      return TRUE;
+    }
+    return FALSE;
   }
 
   /**