Hello, I'm using https://github.com/powerline/powerline and try to add rainbarf. By default it looks like this in `tmux`:  When I now add the rainbarf through my `.tmux.conf, it'll look like this:  As you can see, it'll replace the complete right segement group of Powerline, but i actually want to add it as additional segment in there. Any ideas how to do so? (Please note, I usually have wider shell windows, so the width in the screenshots above is not the issue of this problem) Thanks in advance.