Plugin triggers tmux message

[francescoboc]

Hi, first of all thanks for this plugin! It works very well, but I am having a little annoying issue: when I have vim open in a tmux window and switch to another window, then the window with vim will most of the time send a "message". I attach an image to be clearer.

I am focused on win2 (*), while in win1 there's an instance of vim running. As you can see, there's the hashtag (#) symbol and it's highlited (the blue color is a choice of mine). I usually see this happen when I have a terminal running in a window and then the terminal outputs something, then tmux notifies me that something happened in that window. But with just vim running, this should not happen.