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Tags allow you to mark glyphs so they appear with a small colored bar in the Font Overviews. The same color is shown on the tab bar for glyph edit windows. To tag a glyph, right click on one or more selected glyphs and select one of the tags from the Tag submenu, use the keyboard shortcut keys (Ctrl + 1-5) or drag and drop them from the font overview window onto one of the tag categories. You can view all glyphs that have a tag by selecting the Tagged category from the categories panel or select one of the tag subcategories to view all glyphs that have a specific tag assigned to them.
You can select glyphs with a specific tag through Select Tagged command from the Edit menu.
To untag a glyph, you can either select Tag None, or tag the glyph again.
Note: Each glyph can only have one tag.