diff --git a/wp-admin/update-core.php b/wp-admin/update-core.php
index 3671915d57..df5ea75d01 100644
--- a/wp-admin/update-core.php
+++ b/wp-admin/update-core.php
@@ -412,6 +412,7 @@ if ( 'upgrade-core' == $action ) {
 	wp_version_check();
 	require_once(ABSPATH . 'wp-admin/admin-header.php');
 	core_upgrade_preamble();
+	include(ABSPATH . 'wp-admin/admin-footer.php');
 
 } elseif ( 'do-core-upgrade' == $action || 'do-core-reinstall' == $action ) {
 	check_admin_referer('upgrade-core');
@@ -432,6 +433,8 @@ if ( 'upgrade-core' == $action ) {
 	if ( isset( $_POST['upgrade'] ) )
 		do_core_upgrade($reinstall);
 
+	include(ABSPATH . 'wp-admin/admin-footer.php');
+
 } elseif ( 'do-plugin-upgrade' == $action ) {
 
 	if ( ! current_user_can( 'update_plugins' ) )
@@ -459,6 +462,7 @@ if ( 'upgrade-core' == $action ) {
 	echo '<h2>' . esc_html__('Update Plugins') . '</h2>';
 	echo "<iframe src='$url' style='width: 100%; height: 100%; min-height: 750px;' frameborder='0'></iframe>";
 	echo '</div>';
+	include(ABSPATH . 'wp-admin/admin-footer.php');
 
 } elseif ( 'do-theme-upgrade' == $action ) {
 
@@ -487,6 +491,8 @@ if ( 'upgrade-core' == $action ) {
 	echo '<h2>' . esc_html__('Update Themes') . '</h2>';
 	echo "<iframe src='$url' style='width: 100%; height: 100%; min-height: 750px;' frameborder='0'></iframe>";
 	echo '</div>';
-}
+	include(ABSPATH . 'wp-admin/admin-footer.php');
 
-include(ABSPATH . 'wp-admin/admin-footer.php');
+} else {
+	do_action('update-core-custom_' . $action);
+}
\ No newline at end of file