That empty page you post, says "blocked". This doesn't come from wpForo but from something else, a plugin maybe, Wordfence, who knows.

I see.. you are thinking I am not making it to wpForo page

I have deactivated every single plugin except for wpForo.

I am still unable to run Update User Statistic. It leads to blue screen in FF and to empty blank page in Chrome or Edge. 

Where can I find the logs on my system of why wpForo failing so that I can share that info with you 

Enable standard Wordpress debug to a log and check the debug.log. Post the results if any, here.

Also you can press F12 to chekc your browser console for errors.