Canonical Combining Class - Double Above

Double Above is a numeric value assigned to certain diacritical marks, indicating they should be rendered above the base character and stacked at a vertical position higher than the standard “Above” class. This combining class ensures proper ordering when multiple marks attach to the same base, so that characters with this value are placed after those with lower classes like “Above” but before marks like “Below” or other higher-positioned classes. It is used for marks such as the double acute accent or specific Cyrillic signs, guaranteeing consistent visual stacking and reordering during text normalization, which is critical for correct display and collation of accented text across fonts and platforms.