Undefined Key Warning

After an update of the plugin, some of my users have reported the following error when clicking to edit a page:

Warning: Undefined key “active” in /var/www/…/wp-content/plugins/members/admin/class-notifications.php on line 414

Line 414 in class-notifications.php is:
$active_notifications = $this->get()[‘active’];

I fixed the error by editing the line as follows:
$active_notifications = $this->get()[‘active’] ?? array();

Just letting you know in case it helps for future versions.