A font subset is received that includes one or more glyphs of a master font which has a master ordering that establishes an order of precedence on the glyphs of the master font. When the font subset is received, one or more glyphs already exist in a consecutive sequence in an extensible data structure. In response to receiving the font subset, at least one existing glyph is repositioned in the extensible data structure and each received glyph of the received font subset is positioned in the extensible data structure. The repositioning of the at least one existing glyph and the positioning of each received glyph jointly establish a new consecutive sequential ordering on the glyphs in the extensible data structure, such that the new consecutive sequential ordering preserves on the glyphs in the extensible data structure the order of precedence established by the master ordering.