Well, if you get the browser to simulate a mouseclick on all class='thUp', then you have it. I couldn't do it with only one line of code in the javascript console, and have never worked with any bigger scriptexpansions, so I leave it in the hands of someone else.
This can easily be executed with FireFox and Chrome. For Chrome you press F12, go to the Console tab, paste it and press enter. FireFox uses something similar, but I don't have it on my computer so I can't write it down.