Minimize browser to title bar for ProfitUI

[twixter]

Before I switched to ProfitUI, I used a mix&match of various addons, including Othesus Four Tabbed Browser with bookmarks.
I'm enjoying ProfitUI, but I find minimizing the browser window hides it completely, and clicking the browser button again will most of the time open a new browser window. I have no idea what affects this, but it seems that about 95% of the time, minimize actually closes the window.
I would like the minimize button on the ProfitUI browser to work like it does/did with Othesus' browser addon - unless I'm missing something critical/obvious that would make my request pointless - i.e. minimizing like a curtain being rolled up. Unfortunately, my XML-fu is weak, so I turn to you.

Anyone able to help?