While you're tweaking things, mind increasing the font size? I typically zoom in, but then the up arrows get pixelated. Such problems!
As for the arrows being pixelated, rather than having higher resolution images, shouldn't the images be replaced with unicode?
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NoSquint only seems to be useful if you want to adjust the global zoom level.
https://gist.github.com/dunhamsteve/8572389Or you could do something with Stylish or the like.