Fenix: FNX2-17017 ⁃ Use Firefox Sharp Sans font

[sblatz]

Currently we're not using the custom font Firefox Sharp Sans. This should be implemented before MVP, and is likely a line item in our design audit

Since this is a proprietary font, we cannot include it in our product through GitHub - Instead we will have to include the fonts via the Fenix Build Process on Task Cluster. This work is documented in #1365

[sblatz]

@shorlander mentioned there _may_ be potential legal ramifications by putting this in the app, so let's make sure we address those

[pocmo]

• In the past using custom fonts was a guaranteed way to leak memory - I wonder if that is better today (@colintheshots may know?)
• Our own guidelines recommend to use the system font :) https://design.firefox.com/photon/visuals/typography.html

[shorlander]

* Our own guidelines recommend to use the system font :) https://design.firefox.com/photon/visuals/typography.html

Those guidelines are mostly targeted at Desktop. But also we wrote those guidelines before Material had carved out a lot of space for more flexible theming (https://material.io/design/material-studies/about-our-material-studies.html) :)

[colintheshots]

Google added full, first-party support to add custom fonts in the support library with proper caching a bit over a year ago. Before that point, using custom fonts required various hacks and wasn't well-supported on Android without third-party libraries. Using a proper font cache avoided the memory leaks even before Google made their first-party changes.

[sm4rk0]

Could someone please answer this question from @cadeyrn?

Maybe these are naive questions but I would like to understand the reasons.

Why must a font with such licencing restrictions be used at all in an open source project like Fenix? Apart from the concerns already expressed by @mitchhentges, does it not also make distribution via other channels like F-Droid more challenging? And if it's really so important to use this font is there really no way to get better licencing conditions which are more compatible with Mozilla and their open source culture? There are already other special Mozilla fonts like Fira Sans and Zilla Slab which are also open fonts. Why can't have Firefox Sharp Sans similar conditions?

[fitojb]

Sharp Sans isn’t even suited for UI copy, as e.g. Inter is (Inter is the other new brand font).

[shorlander]

We aren't doing this right now.