Undefined variable if debugging is enabled, fixable with 1 line of code

If you are using this plugin it still works but if you decide to turn on WordPress’s debugging like below:

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);

You’ll be met with an error:

Notice: Undefined variable: wpmu_version in /home/HOSTHERE/public_html/wp-content/plugins/kb-advanced-rss-widget/versions/wp-2-8.php on line 53

Which relates to this bit of code:

if ($wpmu_version)
	define('KBRSS_WPMU', true);
else
	define('KBRSS_WPMU', false); // change here to override and make always true

It should be preceded by global $wpmu_version;

Also surely should be coded like below, with the brackets…:

global $wpmu_version;
if ($wpmu_version) {
	define('KBRSS_WPMU', true);
} else {
	define('KBRSS_WPMU', false); // change here to override and make always true
}

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