wp_admin_bar_wp_menu( WP_Admin_Bar $wp_admin_bar )

function wp_admin_bar_wp_menu( $wp_admin_bar ) {
	if ( current_user_can( 'read' ) ) {
		$about_url = self_admin_url( 'about.php' );
	} elseif ( is_multisite() ) {
		$about_url = get_dashboard_url( get_current_user_id(), 'about.php' );
	} else {
		$about_url = false;
	}

	$cp_logo_src = includes_url( 'images/classicpress-logo-dashicon-grey-on-transparent.svg' );
	$wp_logo_menu_args = array(
		'id'    => 'wp-logo',
		'title' => (
			'<img class="cp-logo" src="' . $cp_logo_src . '" alt="ClassicPress logo" />'
			. '<span class="screen-reader-text">' . __( 'About ClassicPress' ) . '</span>'
		),
		'href'  => $about_url,
	);

	// Set tabindex="0" to make sub menus accessible when no URL is available.
	if ( ! $about_url ) {
		$wp_logo_menu_args['meta'] = array(
			'tabindex' => 0,
		);
	}

	$wp_admin_bar->add_menu( $wp_logo_menu_args );

	if ( $about_url ) {
		// Add "About ClassicPress" link
		$wp_admin_bar->add_menu( array(
			'parent' => 'wp-logo',
			'id'     => 'about',
			'title'  => __('About ClassicPress'),
			'href'   => $about_url,
		) );
	}

	// Add ClassicPress.net link
	$wp_admin_bar->add_menu( array(
		'parent'    => 'wp-logo-external',
		'id'        => 'wporg',
		'title'     => __('ClassicPress.net'),
		'href'      => 'https://www.classicpress.net',
	) );

	// Add documentation link
	$wp_admin_bar->add_menu( array(
		'parent'    => 'wp-logo-external',
		'id'        => 'documentation',
		'title'     => __('Documentation'),
		'href'      => __('https://docs.classicpress.net/'),
	) );

	// Add support link
	$wp_admin_bar->add_menu( array(
		'parent'    => 'wp-logo-external',
		'id'        => 'support',
		'title'     => __('Support'),
		'href'      => __('https://docs.classicpress.net/faq-support/'),
	) );
}