The LanguageFontGroup API should not be confused with a font fallback mechanism. It provides a single font recommendation for a given language, and the assumption is that the text formatted with that font is all in that language. If the content does happen to contain text in another language that that font does not support, then application frameworks provided by Windows will automatically apply a fallback font to those portions of the text when it is rendered. The typographic quality may be less than optimal, however. This shows a comparison of a single font for English being applied to mixed English/Japanese text versus separate recommended fonts being applied to English text and Japanese text.



Font Fallback (recommended font not applied)

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Using Font Mapping (recommended font applied)

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