Firefox has a setting (Preferences -> Content -> Fonts & Colors -> Advanced) that is supposed to let you set font preferences for different character sets. I've tried setting larger minimum font sizes for some non-Western character sets (I'm still learning, and have to see extra detail to tell them apart!) and nothing seems to happen. For example, if there's Hangul on a page (like this one), it will show in the same size as the Latin characters around it, even if I set "minimum font size" to 24.
Am I misunderstanding how that setting is supposed to work, or does it just not do anything? Is there any other way to blow up only non-Western characters while leaving the letters I know how to read intact?