* Add `flat-top` variants for `curly`, `straight-vertical-sides`, and `rounded-vertical-sides` forms of `W` and `w` (#2146).
* Add `almost-flat-top` variants for `curly` forms of `W` and `w`.
* Refine shape of the following characters:
  - GREEK CAPITAL LETTER HETA (`U+0370`).
  - GREEK SMALL LETTER HETA (`U+0371`).
  - LATIN CAPITAL LETTER HALF H (`U+2C75`).
  - LATIN SMALL LETTER HALF H (`U+2C76`).
  - LATIN CAPITAL LETTER AU (`U+A736`).
  - LATIN CAPITAL LETTER REVERSED HALF H (`U+A7F5`).
  - LATIN SMALL LETTER REVERSED HALF H (`U+A7F6`).
  - LATIN SMALL LIGATURE FFI (`U+FB03`).
* Make certain characters slightly wider under Quasi-Proportional. Affected characters:
  - ARMENIAN CAPITAL LETTER TO (`U+0539`).
  - ARMENIAN SMALL LETTER TO (`U+0569`).
  - ARMENIAN SMALL LIGATURE ECH YIWN (`U+0587`).
* Fix variant application of `cv38` on `U+1DF0F`.