I always need a minimum font size and high contrast and, if I need to understand something or follow a discussion, I need some 'clean space'. GH has very low contrast and doesn't adapt well bigger/minimum font sizes (their answer to that was 'use the zoom function instead'). Their UI doesn't work for me at all: I find the site very cluttered and clunky and generally hard to browse. I go there as rarely as possible.
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