I’m not sure what the code causing the error in my sidebar did anyway (HTML and CSS I kind of get, but PHP I don’t have a clue with) and am certainly far too lazy to try and fix it. So I just commented it out. Problem not exactly solved, but hidden, which I consider just as good.

Also I added a CC-BY license. So in other words feel free to steal my work, just make sure to say where you stole it from.