I hear a lot of people like Firefox. To me the appearance looks like a grainy low resolution screen capture. Maybe there is an adjustment for that?
I have been using Firefox almost exclusively for 7-8 years now and think it is a wonderful product. I have never had any issue with resolution. I cannot imagine that it is a Firefox issue at all. There must be something else wrong with your system I would also highly recommend Firefox's sister software, Thunderbird for email.
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