Thanks for replying,
Sorry for replying this late, I don't believe that I got an email regarding your reply.
I have recently started playing with Mattermost again due to the 3.0 update.
Currently when I'm using CentOS 6.8 the popup still pops up a few seconds after closing it.
Does this mean that my Mattermost installation is not working properly and users can not receive messages? If there is a fallback method to deliver messages and other notifcation can I enable that method and disable the popup?
tl;dr: Has there been any change in my question since 2.2 and 3.0?