X-Git-Url: https://scripts.mit.edu/gitweb/autoinstalls/wordpress.git/blobdiff_plain/138998bbd8f7a1ac38b2f1eacbdf7cd522be4b13..HEAD:/wp-includes/customize/class-wp-customize-header-image-setting.php

diff --git a/wp-includes/customize/class-wp-customize-header-image-setting.php b/wp-includes/customize/class-wp-customize-header-image-setting.php
index 98b79aed..af5c5162 100644
--- a/wp-includes/customize/class-wp-customize-header-image-setting.php
+++ b/wp-includes/customize/class-wp-customize-header-image-setting.php
@@ -29,6 +29,15 @@ final class WP_Customize_Header_Image_Setting extends WP_Customize_Setting {
 	public function update( $value ) {
 		global $custom_image_header;
 
+		// If _custom_header_background_just_in_time() fails to initialize $custom_image_header when not is_admin().
+		if ( empty( $custom_image_header ) ) {
+			require_once( ABSPATH . 'wp-admin/custom-header.php' );
+			$args = get_theme_support( 'custom-header' );
+			$admin_head_callback = isset( $args[0]['admin-head-callback'] ) ? $args[0]['admin-head-callback'] : null;
+			$admin_preview_callback = isset( $args[0]['admin-preview-callback'] ) ? $args[0]['admin-preview-callback'] : null;
+			$custom_image_header = new Custom_Image_Header( $admin_head_callback, $admin_preview_callback );
+		}
+
 		// If the value doesn't exist (removed or random),
 		// use the header_image value.
 		if ( ! $value )