If one of your glyphs got damaged and you wish to reset it You can delete the glyph and add it again.
1. Select the glyph you want to delete (when selected the glyph’s background turns red)
2. Make sure that only the glyph you want to delete is selected.
3. In order to add the glyph again Copy the Unicode value of the glyph.
4. Open the Glyphs dialog.
5. Click Remove to delete the selected glyph.
To add the glyph again:
6. Paste the Unicode value of the glyph in the “Character code” input, and click “Enter”! (“Return” if mac) – This will change the Unicode to hex (U+0039 to 0×0039) and a preview of the character will show up.
7. Click ADD and the new empty glyph will appear at the end of the glyphs row.