Are you seeing a difference that dramatic on affected webpages?
Yes, and it might matter for you on what your system settings are. Also, I found another setting in
about:config:
gfx.font_rendering.cleartype.always_use_for_content. This was already set to FALSE for me, so sites with simple text such as EvC were displayed without ClearType. The sites with special formatting, such as the Atlantic article, were the ones affected by the other preference that I mentioned.
Also, I switched the above preference to TRUE, and now everything is in ClearType; you shouldn't have to restart the browser for the effects to kick in, at least I didn't have to.
There appeared to be a little bit of a difference in the fonts of the two browsers. The Firefox fonts appeared a little bit bolder because they were just a tiny bit thicker but that was all. Hitting Ctrl-+ several times didn't make any blurriness apparent in either browser.
I suppose they could be using different techniques to produce the effect. The image I posted was produced in MS Word, the first without ClearType, the second with ClearType. MS's ClearType may not be the same as either FF or Chrome.
Here's part of my samples zoomed in:
The difference should be very noticeable.
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