This feature makes all variations of a selected character accessible. This serves several purposes: An application may not support the feature by which the desired glyph would normally be accessed; the user may need a glyph outside the context supported by the normal substitution, or the user may not know what feature produces the desired glyph. Since many-to-one substitutions are not covered, ligatures would not appear in this table unless they were variant forms of another ligature.

This feature replaces the default (current) forms with the historical alternates, e.g. the long form of s or the old Fraktur k.

Replaces a sequence of glyphs with a single glyph, e.g. 'fi', 'fl'. This feature is enabled by default and cannot currently be disabled.

Some fonts contain both a default form of zero, and an alternative form which uses a diagonal slash through the counter. Especially in condensed designs, it can be difficult to distinguish between 0 and O (zero and capital O) in any situation where capitals and lining figures may be arbitrarily mixed. This feature allows the user to change from the default 0 to a slashed form.