Index: wp-content/themes/twentyseventeen/functions.php
===================================================================
--- wp-content/themes/twentyseventeen/functions.php	(revision 39471)
+++ wp-content/themes/twentyseventeen/functions.php	(working copy)
@@ -103,7 +103,7 @@
  	 */
 	add_editor_style( array( 'assets/css/editor-style.css', twentyseventeen_fonts_url() ) );
 
-	add_theme_support( 'starter-content', array(
+	$starter_content = array(
 		'widgets' => array(
 			'sidebar-1' => array(
 				'text_business_info',
@@ -186,7 +186,9 @@
 				),
 			),
 		),
-	) );
+	);
+
+	add_theme_support( 'starter-content', apply_filters( 'twentyseventeen_starter_content', $starter_content ) );
 }
 add_action( 'after_setup_theme', 'twentyseventeen_setup' );