The font Arial is mapped to Helvetica, but Helvetica on Mac OS X only ships with a single weight. However Helvetica Neue does ship with several weights. I therefore suggest remapping Arial to Helvetica Neue (regular/bold/italic/bold italic) In case my Helvetica Neue fonts aren't quite what come shipped with OS X, I have: UltraLight (+italic) Light (+italic) Regular (+italic) Bold (+italic, +condensed) Black (condensed only)
@Vitor - is this applicable anymore? I think macOS have new 'San Francisco' font these days? https://developer.apple.com/fonts/
We have currently here mapped `Arial` to `Helvetica`: https://searchfox.org/wubkat/rev/18019ceed4fbceaa9fcc23b2f36758831b23a155/Source/WebCore/platform/graphics/FontCache.cpp#156