diff --git a/php/class-post-type.php b/php/class-post-type.php
index 5da9c524..cb23b731 100644
--- a/php/class-post-type.php
+++ b/php/class-post-type.php
@@ -79,6 +79,13 @@ public function hooks() {
 		add_filter( 'content_save_pre', array( $this, 'filter_out_settings_if_removed_in_metabox' ), 10 );
 		add_action( 'admin_print_scripts-revision.php', array( $this, 'disable_revision_ui_for_published_posts' ) );
 		add_action( 'admin_notices', array( $this, 'admin_show_merge_error' ) );
+
+		// Add workaround for failure to save changes to option settings when publishing changeset outside of customizer. See https://core.trac.wordpress.org/ticket/39221#comment:14
+		if ( function_exists( '_wp_customize_publish_changeset' ) && function_exists( 'wp_doing_ajax' ) ) { // Workaround only works in WP 4.7.
+			$priority = has_action( 'transition_post_status', '_wp_customize_publish_changeset' );
+			add_action( 'transition_post_status', array( $this, 'start_pretending_customize_save_ajax_action' ), $priority - 1, 3 );
+			add_action( 'transition_post_status', array( $this, 'finish_pretending_customize_save_ajax_action' ), $priority + 1, 3 );
+		}
 	}
 
 	/**
@@ -588,6 +595,59 @@ public function save( array $args ) {
 		return $r;
 	}
 
+	/**
+	 * Remember whether customize_save is being pretended.
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/39221#comment:14
+	 *
+	 * @var bool
+	 */
+	protected $is_pretending_customize_save_ajax_action = false;
+
+	/**
+	 * Start pretending customize_save Ajax action.
+	 *
+	 * Add workaround for failure to save changes to option settings when publishing changeset outside of customizer.
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/39221#comment:14
+	 * @see \WP_Customize_Manager::doing_ajax()
+	 *
+	 * @param string   $new_status     New post status.
+	 * @param string   $old_status     Old post status.
+	 * @param \WP_Post $changeset_post Changeset post object.
+	 */
+	function start_pretending_customize_save_ajax_action( $new_status, $old_status, $changeset_post ) {
+		$is_publishing_changeset = ( 'customize_changeset' === $changeset_post->post_type && 'publish' === $new_status && 'publish' !== $old_status );
+		if ( ! $is_publishing_changeset || isset( $_REQUEST['action'] ) ) {
+			return;
+		}
+		$this->is_pretending_customize_save_ajax_action = true;
+		add_filter( 'wp_doing_ajax', '__return_true' );
+		$_REQUEST['action'] = 'customize_save';
+	}
+
+	/**
+	 * Finish pretending customize_save Ajax action.
+	 *
+	 * Clean up workaround for failure to save changes to option settings when publishing changeset outside of customizer.
+	 *
+	 * @link https://core.trac.wordpress.org/ticket/39221#comment:14
+	 * @see \WP_Customize_Manager::doing_ajax()
+	 *
+	 * @param string   $new_status     New post status.
+	 * @param string   $old_status     Old post status.
+	 * @param \WP_Post $changeset_post Changeset post object.
+	 */
+	function finish_pretending_customize_save_ajax_action( $new_status, $old_status, $changeset_post ) {
+		$is_publishing_changeset = ( 'customize_changeset' === $changeset_post->post_type && 'publish' === $new_status && 'publish' !== $old_status );
+		if ( ! $is_publishing_changeset || ! $this->is_pretending_customize_save_ajax_action ) {
+			return;
+		}
+		remove_filter( 'wp_doing_ajax', '__return_true' );
+		unset( $_REQUEST['action'] );
+		$this->is_pretending_customize_save_ajax_action = false;
+	}
+
 	/**
 	 * Re-map customize meta cap to edit_theme_options primitive cap.
 	 *
diff --git a/tests/php/test-class-post-type.php b/tests/php/test-class-post-type.php
index fcdff6b7..c6f26248 100644
--- a/tests/php/test-class-post-type.php
+++ b/tests/php/test-class-post-type.php
@@ -663,6 +663,49 @@ public function test_save() {
 		$this->assertEquals( 'future', get_post_status( $post_id ) );
 	}
 
+	/**
+	 * Test that changes to options can be saved by publishing the changeset.
+	 *
+	 * @covers \CustomizeSnapshots\Post_Type::start_pretending_customize_save_ajax_action()
+	 * @covers \CustomizeSnapshots\Post_Type::finish_pretending_customize_save_ajax_action()
+	 */
+	function test_pretending_customize_save_ajax_action() {
+		if ( ! function_exists( 'wp_generate_uuid4' ) ) {
+			$this->markTestSkipped( 'Only relevant to WordPress 4.7 and greater.' );
+		}
+
+		set_current_screen( 'edit' );
+		$this->assertTrue( is_admin() );
+		$post_type = $this->get_new_post_type_instance( $this->plugin->customize_snapshot_manager );
+		$post_type->init();
+
+		$old_sidebars_widgets = get_option( 'sidebars_widgets' );
+		$new_sidebars_widgets = $old_sidebars_widgets;
+		$new_sidebar_1 = array_reverse( $new_sidebars_widgets['sidebar-1'] );
+
+		$post_id = $this->factory()->post->create( array(
+			'post_type' => 'customize_changeset',
+			'post_status' => 'draft',
+			'post_name' => wp_generate_uuid4(),
+			'post_content' => wp_json_encode( array(
+				'sidebars_widgets[sidebar-1]' => array(
+					'value' => $new_sidebar_1,
+				),
+			) ),
+		) );
+
+		// Save the updated sidebar widgets into the options table.
+		wp_publish_post( $post_id );
+
+		// Make sure previewing filters are removed.
+		remove_all_filters( 'option_sidebars_widgets' );
+		remove_all_filters( 'default_option_sidebars_widgets' );
+
+		// Ensure that the value has actually been written to the DB.
+		$updated_sidebars_widgets = get_option( 'sidebars_widgets' );
+		$this->assertEquals( $new_sidebar_1, $updated_sidebars_widgets['sidebar-1'] );
+	}
+
 	/**
 	 * Test granting customize capability.
 	 *