diff --git a/wp-content/themes/twentythirteen/inc/back-compat.php b/wp-content/themes/twentythirteen/inc/back-compat.php
index a10691ecfd..8638adfa49 100644
--- a/wp-content/themes/twentythirteen/inc/back-compat.php
+++ b/wp-content/themes/twentythirteen/inc/back-compat.php
@@ -13,24 +13,18 @@
 
 /**
  * Prevent switching to Twenty Thirteen on old versions of WordPress. Switches
- * to the previously activated theme or the default theme.
+ * to the default theme.
  *
  * @since Twenty Thirteen 1.0
  *
- * @param string $theme_name The theme name.
- * @param WP_Theme $theme The theme object.
  * @return void
  */
-function twentythirteen_switch_theme( $theme_name, $theme ) {
-	if ( 'twentythirteen' != $theme->get_template() )
-		switch_theme( $theme->get_template(), $theme->get_stylesheet() );
-	elseif ( 'twentythirteen' != WP_DEFAULT_THEME )
-		switch_theme( WP_DEFAULT_THEME );
-
+function twentythirteen_switch_theme() {
+	switch_theme( WP_DEFAULT_THEME, WP_DEFAULT_THEME );
 	unset( $_GET['activated'] );
 	add_action( 'admin_notices', 'twentythirteen_upgrade_notice' );
 }
-add_action( 'after_switch_theme', 'twentythirteen_switch_theme', 10, 2 );
+add_action( 'after_switch_theme', 'twentythirteen_switch_theme' );
 
 /**
  * Prints an update nag after an unsuccessful attempt to switch to
@@ -53,6 +47,22 @@ function twentythirteen_upgrade_notice() {
  * @return void
  */
 function twentythirteen_customize() {
-	wp_die( sprintf( __( 'Twenty Thirteen requires at least WordPress version 3.6. You are running version %s. Please upgrade and try again.', 'twentythirteen' ), $GLOBALS['wp_version'] ) . sprintf( ' <a href="javascript:history.go(-1);">%s</a>', __( 'Go back.', 'twentythirteen' ) ) );
+	wp_die( sprintf( __( 'Twenty Thirteen requires at least WordPress version 3.6. You are running version %s. Please upgrade and try again.', 'twentythirteen' ), $GLOBALS['wp_version'] ), '', array(
+		'back_link' => true,
+	) );
 }
 add_action( 'load-customize.php', 'twentythirteen_customize' );
+
+/**
+ * Prevents the Theme Preview from being loaded on WordPress versions prior to 3.4.
+ *
+ * @since Twenty Thirteen 1.0
+ *
+ * @return void
+ */
+function twentythirteen_preview() {
+	if ( isset( $_GET['preview'] ) ) {
+		wp_die( sprintf( __( 'Twenty Thirteen requires at least WordPress version 3.6. You are running version %s. Please upgrade and try again.', 'twentythirteen' ), $GLOBALS['wp_version'] ) );
+	}
+}
+add_action( 'template_redirect', 'twentythirteen_preview' );
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