Does Ubuntu Mate (software boutique) include 3rd party PPA's?

Support & Help Requests
2

Possibly you have not yet updated the welcome center?

welcomeScr.png711×515 226 KB

Which is
/etc/apt/sources.list.d/ubuntu-mate-dev-ubuntu-welcome-xenial.list

On a side note we have a newer tool that you may not know about.
Code:
inxi -r
and/or
man inxi