Seems to still be working fine except for 1 issue I had to fix

This plugin still appears to be working fine with WordPress 5.1.1! It does just what it says it does.

The only problem I had was that it was creating duplicate (two instead of one) notices in in the activity stream when a new user became a member. This was annoying. It was also sending me two emails. Apparently other people had this same problem, and I was able to solve it following the solution provided by Mr3lade on this thread. Problem solved! Will update here if I find any other issues.

https://wordpress.org/support/topic/double-mail/?replies=6
https://wordpress.org/support/topic/double-informations-after-registration/