Realiza una página que contenga un párrafo con fuentes vinculadas,
con la fuente ‘Fira’ del Sistema Operativo de Firefox FiraOpenType,
que puedes descargar aquí:

B2G OS is a community maintained open source operating system
for smartphones, tablets, smart TVs and other connected devices.
The project was started in 2011 and is based on the Linux kernel and
Gecko rendering engine. The entire user interface is built using web technologies
(HTML, CSS and JavaScript) and can be used to launch and use web applications.
Since Mozilla discontinued their commercial Firefox OS smartphone
program the smartphone part of the project is entirely
maintained by Mozilla's volunteer community, and branded as B2G OS.

https://www.mozilla.org/en-US/styleguide/products/firefox-os/typeface/

o la ‘Roboto’ del Sistema Operativo Android que puedes descargar aquí:

Making the web more beautiful, fast, and open through great typography
We believe the best way to bring personality and performance
to websites and products is through great design and technology.
Our goal is to make that process simple, by offering an intuitive
and robust directory of open source designer web fonts.
By using our extensive catalog, you can share and integrate
typography into any design project seamlessly—no matter
where you are in the world.

https://www.mozilla.org/en-US/styleguide/products/firefox-os/typeface/