Variation Selector-73

A variation selector can request a specific glyph after a base character.

An ideographic variation sequence (IVS) is a base followed immediately by its selector. In a registered pair, the selector directs a supporting font to a glyph form while the character's underlying identity stays the same. VS73 has no separate reading. If an editor offers Unicode hexadecimal input, E0138 is the value to enter; the command depends on the editor.

The plain-text problem came first: font choice alone cannot preserve which glyph a text intended. A Unicode proposal dated 2000-08-15 described invisible selectors acting after specified base characters. The later Ideographic Variation Database (IVD) let CJK (Chinese, Japanese, and Korean) collections register forms for regional, publishing, government, and scholarly needs. Adobe-Japan1, a Japanese character collection for fonts, was registered in the IVD on 2007-12-14.

Why does Variation Selector-73 disappear?

Because selectors have no visible mark of their own.

When a base-plus-selector pair is unsupported or unassigned, the base normally displays as it would alone; the selector adds no visible mark.

Fonts can list supported pairs in an OpenType Format 14 character-map table, a list of base-and-selector combinations. If the app or font does not support a pair, the requested glyph form may not appear.

Don't assign VS73 a private meaning

A portable character variation must be a sequence Unicode defines or registers. Adding VS73 after an arbitrary character does not create a reliable private style code; another application can ignore the pair.

Use a documented sequence when the text needs a specific glyph form. A private convention needs a separate format that both sides understand.