Indeed it has. Thanks for your help and fast support. Have a nice day.

What you're looking for is implemented in the widget "forum stats", in which you can view the number of posts and number of topics on any page. I'm not a plugin developer (read: javascript noob 8)), but I think it's respectively easy to get this done in a similar fashion. I'd recommend looking up the way the module "nodebb-widget-essentials" deals with this. I assume it's easy to API'ify this.

I'm quite sure I did, but juste in case I will check again.