pin what happens if you install font-awesome (both ttf and otf)?
You can use use the venerable xfd, the X Font Display program (on NetBSD, not there on FreeBSD--why do they remove these useful old programs? xlsfonts is missing too), to check if the glyphs you want are present and what they look like. Note: xfd doesn't work with emojis; which is why, I think, we have nerdfonts.
Take this ncspot case for instance:
$ fgrep -r '\u{' ncspot-master/
ncspot-master/src/album.rs: "\u{f62b} "
ncspot-master/src/artist.rs: "\u{f62b} "
ncspot-master/src/playlist.rs: "\u{f62b} "
ncspot-master/src/show.rs: "\u{f62b} "
ncspot-master/src/track.rs: "\u{f62b} "
ncspot-master/src/ui/statusbar.rs: PlayerEvent::Playing => "\u{f909} ",
ncspot-master/src/ui/statusbar.rs: PlayerEvent::Paused => "\u{f8e3} ",
ncspot-master/src/ui/statusbar.rs: PlayerEvent::Stopped | PlayerEvent::FinishedTrack => "\u{f9da} ",
ncspot-master/src/ui/statusbar.rs: "\u{f9e5} "
ncspot-master/src/ui/statusbar.rs: RepeatSetting::RepeatPlaylist => "\u{f955} ",
ncspot-master/src/ui/statusbar.rs: RepeatSetting::RepeatTrack => "\u{f957} ",
ncspot-master/src/ui/statusbar.rs: "\u{f99c} "
ncspot-master/src/ui/statusbar.rs: // "\u{f62b} "
So, it looks like ncspot uses Unicode code points 0xf62b, 0xf909, 0xf8e3, 0xf9e5, 0xf955, 0xf957 and 0xf99c if use_nerdfonts is enabled. Check if they are present in the fonts we want:
# pkgin install awesome-otf
$ fc-list | fgrep Awesome
/usr/pkg/share/fonts/X11/OTF/Font Awesome 5 Brands-Regular-400.otf: Font Awesome 5 Brands,Font Awesome 5 Brands Regular:style=Regular
/usr/pkg/share/fonts/X11/OTF/Font Awesome 5 Free-Regular-400.otf: Font Awesome 5 Free,Font Awesome 5 Free Regular:style=Regular
/usr/pkg/share/fonts/X11/OTF/Font Awesome 5 Free-Solid-900.otf: Font Awesome 5 Free,Font Awesome 5 Free Solid:style=Solid
$
So, there are 3 Awesome fonts installed. Check each of them using xfd:
$ xfd -fa 'Font Awesome 5 Free,Font Awesome 5 Free Regular:style=Regular'
This one is out right away because the maximum range of code points for this font file is 0xf5c8. Check the Solid style:
$ xfd -fa 'Font Awesome 5 Free,Font Awesome 5 Free Solid:style=Solid'
Aha! this one goes up to 0xf773, so at least one of the code points 0xf62b might be present. Click next and note the upper left: field. But, alas! 0xf62b is blank.
# pkgin remove awesome-otf
You can use xfd to check, similarly, if Kanji, Hanzi, Hangul, ... code points are present in the fonts you are using when you find Firefox displaying tiny boxes-with-hex instead of those glyphs.
