Add the following fonts:
* Comic (Comic Relief)
* Slab Sans (Anton)
* Slab Serif (Rokkitt)
* Formal Serif (Lora)
* Formal Cursive (Petit Formal Script)
* Print (Kalam)
* Hand (Indie Flower)
* Narrow (Archivo Narrow)
* Blackletter (Unifraktur Maguntia)
Add the following font aliases:
* Comic Sans MS is aliased to Comic Relief.
* Arial Narrow is aliased to Archivo Narrow.
* Rockwell is aliased to Rokkitt.
* Impact is aliased to Anton.
Very old browsers (in particular, Firefox 16 and iOS 8.4 Safari) don't
support flexbox without prefixes, which breaks sidebar and comment
layouts. Extend the browserlist config so that autoprefixer generates
flexbox prefixes for these browsers.
