diff --git a/modules/calypsoify/class.jetpack-calypsoify.php b/modules/calypsoify/class.jetpack-calypsoify.php
index 293636135f4ad..f3937495f20ef 100644
--- a/modules/calypsoify/class.jetpack-calypsoify.php
+++ b/modules/calypsoify/class.jetpack-calypsoify.php
@@ -4,6 +4,7 @@
  * Ported from an internal Automattic plugin.
  */
 
+use Automattic\Jetpack\Dashboard_Customizations\Masterbar;
 use Automattic\Jetpack\Redirect;
 use Automattic\Jetpack\Status;
 
@@ -76,8 +77,8 @@ public function admin_color_override( $color ) {
 	}
 
 	public function mock_masterbar_activation() {
-		include_once JETPACK__PLUGIN_DIR . 'modules/masterbar/masterbar.php';
-		new A8C_WPCOM_Masterbar;
+		include_once JETPACK__PLUGIN_DIR . 'modules/masterbar/masterbar/class-masterbar.php';
+		new Masterbar();
 	}
 
 	public function remove_core_menus() {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 4bde03b85c4d1..f366b871676cf 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -30,6 +30,9 @@
 		<testsuite name="comment-likes">
 			<directory prefix="test" suffix=".php">tests/php/modules/comment-likes</directory>
 		</testsuite>
+		<testsuite name="calypsoify">
+			<directory prefix="test" suffix=".php">tests/php/modules/calypsoify</directory>
+		</testsuite>
 		<testsuite name="likes">
 			<directory prefix="test_" suffix=".php">tests/php/modules/likes</directory>
 		</testsuite>
diff --git a/tests/php/modules/calypsoify/test-class.jetpack-calypsoify.php b/tests/php/modules/calypsoify/test-class.jetpack-calypsoify.php
new file mode 100644
index 0000000000000..1847fbca84fd9
--- /dev/null
+++ b/tests/php/modules/calypsoify/test-class.jetpack-calypsoify.php
@@ -0,0 +1,37 @@
+<?php
+/**
+ * Class Calypsoify.
+ *
+ * @package Jetpack
+ */
+
+require_jetpack_file( 'modules/calypsoify/class.jetpack-calypsoify.php' );
+
+/**
+ * Class WP_Test_Jetpack_Calypsoify
+ */
+class WP_Test_Jetpack_Calypsoify extends WP_UnitTestCase {
+
+	/**
+	 * Sets up each test.
+	 *
+	 * @inheritDoc
+	 */
+	public function setUp() {
+		parent::setUp();
+		$this->instance = Jetpack_Calypsoify::getInstance();
+	}
+
+	/**
+	 * Sets up the Masterbar mock.
+	 *
+	 * For sites when Masterbar is not active, we mock it. This test confirms that functions.
+	 *
+	 * @covers Jetpack_Calypsoify::mock_masterbar_activation
+	 * @see https://github.com/Automattic/jetpack/pull/17939
+	 */
+	public function test_mock_masterbar_activation() {
+		$this->instance->mock_masterbar_activation();
+		$this->assertTrue( class_exists( '\Automattic\Jetpack\Dashboard_Customizations\Masterbar' ) );
+	}
+}