Font is not fully importing. Missing ligatures. Outputs as non-monospace

[HolbyFPV]

I am trying to add a ligature to the JetBrainsMono Nerd Font without changing the rest of the font.
https://www.nerdfonts.com/font-downloads

I notice when I import the font, the ligature table is empty. I tried with a different font that I know has ligatures, and again it's empty. I go ahead and add my ligature, which works fine when exported. But none of the original ligatures are there.

Another thing I notice is my terminal no longer detects it as a monospace font. I verified this by exporting the font after importing without making any changes.

Is there an issue with the import process or something I'm missing?

[johanmattssonm]

Thank you for the report. The ligature issue happens because I haven't written a gsub parser yet and it would take quite a while to get such thing in place. I apologize for the inconvenience.

I guess the monospace issue should be easier. Which program should I use to double check this? (and where do i find that value?)

[HolbyFPV]

That is unfortunate, I feel very out of options at the moment. Do you happen to know of any other programs I could use to accomplish this? I have tried FontForge but it crashes when trying to export the font. I'm pretty sure they aren't importing ligatures either. I have no access to OSX so I can't use GlyphsApp.

If you want to investigate the monospace issue, I was using Windows Terminal > Settings > Defaults > Appearance > Font Face. When the "Show all fonts" checkbox is false, it will only show monospace fonts. I don't know how exactly they are detecting if a font is monospace or not.

If I'm using the font exported from Birdfont, I get this warning, and have to check "Show all fonts" in order to see it, indicating that it's not being picked up as monospace. If I use the stock font without running it through Birdfont, no warning or checkbox needed.

[johanmattssonm]

Thanks! The a fix for mono issue will be available in the next release.

[HolbyFPV]

Appreciate it. Hope to see the gsub parser implemented one day 😄