Ensure text remains visible during webfont load

[jonasfj]

According to: https://developers.google.com/speed/pagespeed/insights/?url=http%3A%2F%2Fpub.dartlang.org%2Fpackages%2Fhttp

We have work to: "Ensure text remains visible during webfont load".

"Leverage the font-display CSS feature to ensure text is user-visible while webfonts are loading" See: https://developers.google.com/web/updates/2016/02/font-display

[jonasfj]

Also do we need 4 different weights of the font? I don't know, I'm just wondering..

[sigurdm]

Might still be valid