site_admin_notice(): void|false

685function site_admin_notice() {686	global $wp_db_version, $pagenow;687 688	if ( ! current_user_can( 'upgrade_network' ) ) {689		return false;690	}691 692	if ( 'upgrade.php' === $pagenow ) {693		return;694	}695 696	if ( (int) get_site_option( 'wpmu_upgrade_site' ) !== $wp_db_version ) {697		$upgrade_network_message = sprintf(698			/* translators: %s: URL to Upgrade Network screen. */699			__( 'Thank you for Updating! Please visit the <a href="%s">Upgrade Network</a> page to update all your sites.' ),700			esc_url( network_admin_url( 'upgrade.php' ) )701		);702 703		wp_admin_notice(704			$upgrade_network_message,705			array(706				'type'               => 'warning',707				'additional_classes' => array( 'update-nag', 'inline' ),708				'paragraph_wrap'     => false,709			)710		);711	}712}