Hi

I had the same issue. I reported it to tracker and what have you, and nobody responded. I ended up doing a hack in /mod/riverdashboard/views/default/riverdashboard/nav.php

After line 14 "if (!empty($vars['config']->registered_entities)) {" I inserted this code:

// Ugly fix for missing discussions filter
if (is_plugin_enabled('groups')){
$keyname = 'item:object:groupforumtopic';
$contents[$keyname] = "object,groupforumtopic";
}
// Ugly fix end

Thank you! That helped me very much. 

Hi slyhne!

I need your help again! I want that my activity widget only shows discussions. Do you have a solution for this?