public function export_preview_data() {
		global $wp_registered_sidebars, $wp_registered_widgets;

		$switched_locale = switch_to_locale( get_user_locale() );
		$l10n            = array(
			'widgetTooltip' => __( 'Shift-click to edit this widget.' ),
		);
		if ( $switched_locale ) {
			restore_previous_locale();
		}

		// Prepare Customizer settings to pass to JavaScript.
		$settings = array(
			'renderedSidebars'            => array_fill_keys( array_unique( $this->rendered_sidebars ), true ),
			'renderedWidgets'             => array_fill_keys( array_keys( $this->rendered_widgets ), true ),
			'registeredSidebars'          => array_values( $wp_registered_sidebars ),
			'registeredWidgets'           => $wp_registered_widgets,
			'l10n'                        => $l10n,
			'selectiveRefreshableWidgets' => $this->get_selective_refreshable_widgets(),
		);
		foreach ( $settings['registeredWidgets'] as &$registered_widget ) {
			unset( $registered_widget['callback'] ); // may not be JSON-serializeable
		}

		?>
		<script type="text/javascript">
			var _wpWidgetCustomizerPreviewSettings = <?php echo wp_json_encode( $settings ); ?>;
		</script>
		<?php
	}