diff --git src/bp-blogs/classes/class-bp-blogs-recent-posts-widget.php src/bp-blogs/classes/class-bp-blogs-recent-posts-widget.php
index 8f647ba56..e71e88fff 100644
--- src/bp-blogs/classes/class-bp-blogs-recent-posts-widget.php
+++ src/bp-blogs/classes/class-bp-blogs-recent-posts-widget.php
@@ -12,17 +12,23 @@ defined( 'ABSPATH' ) || exit;
 
 /**
  * The Recent Networkwide Posts widget.
+ *
+ * @since 1.0.0
  */
 class BP_Blogs_Recent_Posts_Widget extends WP_Widget {
 
 	/**
 	 * Constructor method.
+	 *
+	 * @since 1.5.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		$widget_ops = array(
 			'description'                 => __( 'A list of recently published posts from across your network.', 'buddypress' ),
 			'classname'                   => 'widget_bp_blogs_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		);
 		parent::__construct( false, $name = _x( '(BuddyPress) Recent Networkwide Posts', 'widget name', 'buddypress' ), $widget_ops );
 	}
diff --git src/bp-core/classes/class-bp-core-login-widget.php src/bp-core/classes/class-bp-core-login-widget.php
index 6e975d019..b9c66cbd9 100644
--- src/bp-core/classes/class-bp-core-login-widget.php
+++ src/bp-core/classes/class-bp-core-login-widget.php
@@ -21,6 +21,7 @@ class BP_Core_Login_Widget extends WP_Widget {
 	 * Constructor method.
 	 *
 	 * @since 1.9.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		parent::__construct(
@@ -30,6 +31,7 @@ class BP_Core_Login_Widget extends WP_Widget {
 				'description'                 => __( 'Show a Log In form to logged-out visitors, and a Log Out link to those who are logged in.', 'buddypress' ),
 				'classname'                   => 'widget_bp_core_login_widget buddypress widget',
 				'customize_selective_refresh' => true,
+				'show_instance_in_rest'       => true,
 			)
 		);
 	}
diff --git src/bp-friends/classes/class-bp-core-friends-widget.php src/bp-friends/classes/class-bp-core-friends-widget.php
index 8ca38d068..bf8fe2fd1 100644
--- src/bp-friends/classes/class-bp-core-friends-widget.php
+++ src/bp-friends/classes/class-bp-core-friends-widget.php
@@ -21,12 +21,14 @@ class BP_Core_Friends_Widget extends WP_Widget {
 	 * Class constructor.
 	 *
 	 * @since 1.9.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	function __construct() {
 		$widget_ops = array(
 			'description'                 => __( 'A dynamic list of recently active, popular, and newest Friends of the displayed member.  Widget is only shown when viewing a member profile.', 'buddypress' ),
 			'classname'                   => 'widget_bp_core_friends_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		);
 		parent::__construct( false, $name = _x( '(BuddyPress) Friends', 'widget name', 'buddypress' ), $widget_ops );
 
diff --git src/bp-groups/classes/class-bp-groups-widget.php src/bp-groups/classes/class-bp-groups-widget.php
index 08eadf14e..d539355d7 100644
--- src/bp-groups/classes/class-bp-groups-widget.php
+++ src/bp-groups/classes/class-bp-groups-widget.php
@@ -21,12 +21,14 @@ class BP_Groups_Widget extends WP_Widget {
 	 * Working as a group, we get things done better.
 	 *
 	 * @since 1.0.3
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		$widget_ops = array(
 			'description'                 => __( 'A dynamic list of recently active, popular, newest, or alphabetical groups', 'buddypress' ),
 			'classname'                   => 'widget_bp_groups_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		);
 		parent::__construct( false, _x( '(BuddyPress) Groups', 'widget name', 'buddypress' ), $widget_ops );
 
diff --git src/bp-members/classes/class-bp-core-members-widget.php src/bp-members/classes/class-bp-core-members-widget.php
index b50bc2dbf..63d8b2072 100644
--- src/bp-members/classes/class-bp-core-members-widget.php
+++ src/bp-members/classes/class-bp-core-members-widget.php
@@ -21,6 +21,7 @@ class BP_Core_Members_Widget extends WP_Widget {
 	 * Constructor method.
 	 *
 	 * @since 1.5.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 
@@ -33,6 +34,7 @@ class BP_Core_Members_Widget extends WP_Widget {
 			'description'                 => $description,
 			'classname'                   => 'widget_bp_core_members_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		) );
 
 		if ( is_customize_preview() || is_active_widget( false, false, $this->id_base ) ) {
diff --git src/bp-members/classes/class-bp-core-recently-active-widget.php src/bp-members/classes/class-bp-core-recently-active-widget.php
index 9c8408920..2d395fb15 100644
--- src/bp-members/classes/class-bp-core-recently-active-widget.php
+++ src/bp-members/classes/class-bp-core-recently-active-widget.php
@@ -21,6 +21,7 @@ class BP_Core_Recently_Active_Widget extends WP_Widget {
 	 * Constructor method.
 	 *
 	 * @since 1.5.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		$name        = _x( '(BuddyPress) Recently Active Members', 'widget name', 'buddypress' );
@@ -29,6 +30,7 @@ class BP_Core_Recently_Active_Widget extends WP_Widget {
 			'description'                 => $description,
 			'classname'                   => 'widget_bp_core_recently_active_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		) );
 	}
 
diff --git src/bp-members/classes/class-bp-core-whos-online-widget.php src/bp-members/classes/class-bp-core-whos-online-widget.php
index 3e98d3259..31dfccef8 100644
--- src/bp-members/classes/class-bp-core-whos-online-widget.php
+++ src/bp-members/classes/class-bp-core-whos-online-widget.php
@@ -14,6 +14,7 @@ defined( 'ABSPATH' ) || exit;
  * Who's Online Widget.
  *
  * @since 1.0.3
+ * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
  */
 class BP_Core_Whos_Online_Widget extends WP_Widget {
 
@@ -21,6 +22,7 @@ class BP_Core_Whos_Online_Widget extends WP_Widget {
 	 * Constructor method.
 	 *
 	 * @since 1.5.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		$name        = _x( "(BuddyPress) Who's Online", 'widget name', 'buddypress' );
@@ -29,6 +31,7 @@ class BP_Core_Whos_Online_Widget extends WP_Widget {
 			'description'                 => $description,
 			'classname'                   => 'widget_bp_core_whos_online_widget buddypress widget',
 			'customize_selective_refresh' => true,
+			'show_instance_in_rest'       => true,
 		) );
 	}
 
diff --git src/bp-messages/classes/class-bp-messages-sitewide-notices-widget.php src/bp-messages/classes/class-bp-messages-sitewide-notices-widget.php
index 5ea3ff64b..b215d8f6e 100644
--- src/bp-messages/classes/class-bp-messages-sitewide-notices-widget.php
+++ src/bp-messages/classes/class-bp-messages-sitewide-notices-widget.php
@@ -19,6 +19,9 @@ class BP_Messages_Sitewide_Notices_Widget extends WP_Widget {
 
 	/**
 	 * Constructor method.
+	 *
+	 * @since 1.9.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	function __construct() {
 		parent::__construct(
@@ -28,6 +31,7 @@ class BP_Messages_Sitewide_Notices_Widget extends WP_Widget {
 				'classname'                   => 'widget_bp_core_sitewide_messages buddypress widget',
 				'description'                 => __( 'Display Sitewide Notices posted by the site administrator', 'buddypress' ),
 				'customize_selective_refresh' => true,
+				'show_instance_in_rest'       => true,
 			)
 		);
 	}
diff --git src/bp-templates/bp-nouveau/includes/activity/widgets.php src/bp-templates/bp-nouveau/includes/activity/widgets.php
index 206c2d7bc..3358c070d 100644
--- src/bp-templates/bp-nouveau/includes/activity/widgets.php
+++ src/bp-templates/bp-nouveau/includes/activity/widgets.php
@@ -19,6 +19,7 @@ class BP_Latest_Activities extends WP_Widget {
 	 * Construct the widget.
 	 *
 	 * @since 3.0.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 
@@ -34,6 +35,7 @@ class BP_Latest_Activities extends WP_Widget {
 				'classname'                   => 'bp-latest-activities buddypress',
 				'description'                 => __( 'Display the latest updates of your community having the types of your choice.', 'buddypress' ),
 				'customize_selective_refresh' => true,
+				'show_instance_in_rest'       => true,
 			)
 		);
 
diff --git src/bp-templates/bp-nouveau/includes/classes.php src/bp-templates/bp-nouveau/includes/classes.php
index 7a34e9ef9..e898bc8e8 100644
--- src/bp-templates/bp-nouveau/includes/classes.php
+++ src/bp-templates/bp-nouveau/includes/classes.php
@@ -191,11 +191,13 @@ class BP_Nouveau_Object_Nav_Widget extends WP_Widget {
 	 * Constructor
 	 *
 	 * @since 3.0.0
+	 * @since 9.0.0 Adds the `show_instance_in_rest` property to Widget options.
 	 */
 	public function __construct() {
 		$widget_ops = array(
-			'description' => __( 'Displays BuddyPress primary nav in the sidebar of your site. Make sure to use it as the first widget of the sidebar and only once.', 'buddypress' ),
-			'classname'   => 'widget_nav_menu buddypress_object_nav',
+			'description'           => __( 'Displays BuddyPress primary nav in the sidebar of your site. Make sure to use it as the first widget of the sidebar and only once.', 'buddypress' ),
+			'classname'             => 'widget_nav_menu buddypress_object_nav',
+			'show_instance_in_rest' => true,
 		);
 
 		parent::__construct(