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The class manager allows you to manage the classes used in the OpenType Designer. Here you can add, delete and rename classes and add or remove the glyphs in the class. Please note that when you delete a class, add or remove any of its members, the lookups associated with the class will also be changed. This means for example that when you add or remove a glyph to/from a class, the associated kerning pairs will also be added or removed automatically.
Tip: While adding class members, you can filter by anchor class. This is mostly useful when defining mark-to-mark or mark-to-base classes.
The cleanup button in the toolbar will delete all classes that are not used by any of the lookups.
Tip: Use the edit box above the classes listbox to filter the list.
Note: In general the order in which items appear in a class is not important for glyph positioning, however for glyph substitutions it is.