$network_wide parameter always ” in registered activation hook function

Hello,

In my plugin code I am registering my activation and deactivation hook functions, each with the $network_wide parameter as this is intended to be a multisite plugin.

function my_activation_hook($network_wide) {
	if ($network_wide) {
		//do something on all sites
	}
	else {
		//do something on current site
	}
}

function my_deactivation_hook($network_wide) {
	if ($network_wide) {
		//do something on all sites
	}
	else {
		//do something on current site
	}
}

register_activation_hook(__FILE__, 'my_activation_hook');
register_deactivation_hook(__FILE__, 'my_deactivation_hook');

In the deactivation hook the $network_wide parameter is passed as expected i.e. boolean true when network deactivated and boolean false when deactivated on a site. However, in the activation hook, the parameter is always a blank string ”. Has anyone else experienced this? I have tried this on multiple installations (windows and linux) and it seems consistent in the 4.9.4 version at least.

Thanks,
Asif