Why do my folders in instapaper threestyled always disappear?

I’ve installed instapaper threestyled for my instapaper fluid app, and everything is working well..until I quit the app, and relaunch it. Every time I open the application again, my folders bar on the left side is gone. I have to go to the tool bar, click on the browsa butto, and then it reappears. Does anyone know why it is doing this? I want my folders bar to appear automatically on launch.
http://userscripts.org/scripts/show/59955 that’s the link to threestyled and its instruction, which I followed.