understrap/inc/wpcom.php

<?php
/**
 * WordPress.com-specific functions and definitions.
 *
 * This file is centrally included from `wp-content/mu-plugins/wpcom-theme-compat.php`.
 *
 * @package understrap
 */

/**
 * Adds support for wp.com-specific theme functions.
 *
 * @global array $themecolors
 */
if ( ! function_exists ( 'understrap_wpcom_setup' ) ) {
	function understrap_wpcom_setup() {
		global $themecolors;

		// Set theme colors for third party services.
		if ( ! isset( $themecolors ) ) {
			$themecolors = array(
				'bg'     => '',
				'border' => '',
				'text'   => '',
				'link'   => '',
				'url'    => '',
			);
		}
	}
}
add_action( 'after_setup_theme', 'understrap_wpcom_setup' );