Maybe switch to Fira GO

[madig]

https://bboxtype.com/projects/#FiraGO

https://github.com/bBoxType/FiraGO/blob/master/FiraGO_FiraSans_Comparison.pdf

[isantop]

@cassidyjames Thoughts?

[btegs]

I found this issue just now and way past the question date, but I have also been curious about this font. Either you can help push to get it included upstream in Debian or simply add to the main
Pop!_OS PPA.

[frankstrater]

I recommend looking into this, because users are experiencing some issues on older hardware:

bBoxType/FiraSans#23
https://www.reddit.com/r/pop_os/comments/gmuoml/fira_sans_font_weird_the_numbers_1_and_2_are/

I tweaked my 20.04 install on a Thinkpad x220 by picking FiraGo as font for their Fira Sans counterparts, which solved the issue for me.

[madig]

I wouldn't call it an issue on older hardware. The FreeType autohinter (active when hinting is "slight") can be picky about outline details. Those numbers probably have tops that are just slightly outside the top area of other numbers, so the autohinter does not consider them and you get weird height inconsistencies depending on font size.

[sun95n]

I had this problem when installing fira in Cinnamon 20. I was able to solve it by setting None in Hinting (Font Configuration) It seems that this option makes the font longer something that affects the numbers in a strange way.

[andy0130tw]

Same on @madig. The problem can be solved simply by changing the fonts to TTF (maybe with ttfautohint). Setting hinting to "None", on the other hand, affects all fonts in the system.