Something is wrong with font rendering. But the good news is, the same glitches are visible in system bitmap font. I was thinking before that this is caused by bitmap system font which isn't designed to be displayed on bright backgrounds (OSDSYS/HDD OSD are dark) but rather no. In case of vector fonts, it looks like not enough anti-aliassing on letters. But system font have very similar issues. Maybe another kind of filtering is turned on (like sharpening, I dunno)?
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