Currently, libxft is using font->public.max_advance_width to get the width of glyphs. But this is not the case in CJK environments. CJK fonts often include both full-width and half-width glyphs, while those glyphs are using different width of course. public.max_advance_width makes all the half-width glyphs become wider.
Please do not use font->public.max_advance_width, try glyphslot->metrics.vertAdvance and glyphslot->metrics.horiAdvance instead.
*** This bug has been marked as a duplicate of 2715 ***
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