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<?php

/**
 * Twenty Fifteen back compat functionality
 *
 * Prevents Twenty Fifteen from running on WordPress versions prior to 4.1,
 * since this theme is not meant to be backward compatible beyond that and
 * relies on many newer functions and markup changes introduced in 4.1.
 *
 * @package WordPress
 * @subpackage Twenty_Fifteen
 * @since Twenty Fifteen 1.0
 */

/* function twentyfifteen_switch_theme() – Prevent switching to Twenty Fifteen on old versions of WordPress. */
add_action( 'after_switch_theme', 'twentyfifteen_switch_theme' );

/* function twentyfifteen_upgrade_notice() – Add message for unsuccessful theme switch. */

/* function twentyfifteen_customize() – Prevent the Customizer from being loaded on WordPress versions prior to 4.1. */
add_action( 'load-customize.php', 'twentyfifteen_customize' );

/* function twentyfifteen_preview() – Prevent the Theme Preview from being loaded on WordPress versions prior to 4.1. */
add_action( 'template_redirect', 'twentyfifteen_preview' );
 

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