commit ea7dae982a262b2f263a38bf8325d674ae815dde
Author: Andy Postnikov <apostnikov@gmail.com>
Date:   Thu Apr 18 03:45:46 2013 +0400

    Issue #1561352 by andypost, mokaspar, liquidcms: Add field ui support for user form and user display.

diff --git a/masquerade.module b/masquerade.module
index fb76bce..213d928 100644
--- a/masquerade.module
+++ b/masquerade.module
@@ -210,6 +210,23 @@ function masquerade_user_is_masquerading() {
 }
 
 /**
+ * Implements hook_field_extra_fields().
+ */
+function masquerade_field_extra_fields() {
+  $return['user']['user']  = array(
+    'display' => array(
+      'masquerade' => array(
+        'label' => t('Masquerade'),
+        'description' => t('Masquerade as user link.'),
+        'weight' => 50,
+      ),
+    ),
+  );
+
+  return $return;
+}
+
+/**
  * Implements hook_user_view().
  */
 function masquerade_user_view(User $account, $display, $view_mode, $langcode) {