diff -u b/media.file_default_displays.inc /dev/null
--- b/media.file_default_displays.inc
+++ /dev/null
@@ -1,16 +0,0 @@
-<?php
-
-/**
- * @file
- * Default display configuration for the default file types.
- */
-
-/**
- * Implements hook_file_default_displays_alter().
- */
-function media_file_default_displays_alter(&$file_displays) {
-  // Image previews should be displayed using the media image style.
-  if (isset($file_displays['image__preview__file_field_image'])) {
-    $file_displays['image__preview__file_field_image']->settings['image_style'] = 'media_thumbnail';
-  }
-}
diff -u b/media.install b/media.install
--- b/media.install
+++ b/media.install
@@ -68,6 +68,16 @@
   variable_del('media_zindex');
   variable_del('media_backgroundcolor');
   variable_del('media_opacity');
+
+  // Revert to preview's default image_style.
+  $file_displays = file_displays_load('image', 'preview');
+  if (isset($file_displays['image__preview__file_field_image'])) {
+    // Only revert if the style is configured to use media's.
+    if ($file_displays['image__preview__file_field_image']->settings['image_style'] == 'media_thumbnail') {
+      $file_displays['image__preview__file_field_image']->settings['image_style'] = 'thumbnail';
+      file_display_save((object) $file_displays['image__preview__file_field_image']);
+    }
+  }
 }
 
 /**
@@ -1215,2 +1225,9 @@
   }
+
+  // Switch to use media's preview rather than the default.
+  $file_displays = file_displays_load('image', 'preview');
+  if (isset($file_displays['image__preview__file_field_image'])) {
+    $file_displays['image__preview__file_field_image']->settings['image_style'] = 'media_thumbnail';
+    file_display_save((object) $file_displays['image__preview__file_field_image']);
+  }
 }