The following glyph names are referenced but are missing from the glyph set: underscore.alt

[labs-dlugo]

build.sh
Building OperatorMonoSSmLig-Bold
ttx
Dumping "./original/OperatorMonoSSm-Bold.otf" to "./original/OperatorMonoSSm-Bold.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-Bold.ttx
Building ligature font file ./build/OperatorMonoSSmLig-Bold.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-Bold.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-Bold.ttx" to "./build/OperatorMonoSSmLig-Bold.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-Bold.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-BoldItalic
ttx
Dumping "./original/OperatorMonoSSm-BoldItalic.otf" to "./original/OperatorMonoSSm-BoldItalic.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-BoldItalic.ttx
Building ligature font file ./build/OperatorMonoSSmLig-BoldItalic.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-BoldItalic.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-BoldItalic.ttx" to "./build/OperatorMonoSSmLig-BoldItalic.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-BoldItalic.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-Book
ttx
Dumping "./original/OperatorMonoSSm-Book.otf" to "./original/OperatorMonoSSm-Book.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-Book.ttx
Building ligature font file ./build/OperatorMonoSSmLig-Book.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* w_w_w.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_equal.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
* w.spacer
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-Book.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-Book.ttx" to "./build/OperatorMonoSSmLig-Book.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-Book.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-BookItalic
ttx
Dumping "./original/OperatorMonoSSm-BookItalic.otf" to "./original/OperatorMonoSSm-BookItalic.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-BookItalic.ttx
Building ligature font file ./build/OperatorMonoSSmLig-BookItalic.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* w_w_w.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
* w.spacer
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-BookItalic.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-BookItalic.ttx" to "./build/OperatorMonoSSmLig-BookItalic.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-BookItalic.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-Light
ttx
Dumping "./original/OperatorMonoSSm-Light.otf" to "./original/OperatorMonoSSm-Light.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-Light.ttx
Building ligature font file ./build/OperatorMonoSSmLig-Light.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-Light.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-Light.ttx" to "./build/OperatorMonoSSmLig-Light.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-Light.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-LightItalic
ttx
Dumping "./original/OperatorMonoSSm-LightItalic.otf" to "./original/OperatorMonoSSm-LightItalic.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-LightItalic.ttx
Building ligature font file ./build/OperatorMonoSSmLig-LightItalic.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-LightItalic.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-LightItalic.ttx" to "./build/OperatorMonoSSmLig-LightItalic.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-LightItalic.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-Medium
ttx
Dumping "./original/OperatorMonoSSm-Medium.otf" to "./original/OperatorMonoSSm-Medium.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-Medium.ttx
Building ligature font file ./build/OperatorMonoSSmLig-Medium.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-Medium.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-Medium.ttx" to "./build/OperatorMonoSSmLig-Medium.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-Medium.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)
Building OperatorMonoSSmLig-MediumItalic
ttx
Dumping "./original/OperatorMonoSSm-MediumItalic.otf" to "./original/OperatorMonoSSm-MediumItalic.ttx"...
Dumping 'GlyphOrder' table...
Dumping 'head' table...
Dumping 'hhea' table...
Dumping 'maxp' table...
Dumping 'OS/2' table...
Dumping 'name' table...
Dumping 'cmap' table...
Dumping 'post' table...
Dumping 'CFF ' table...
Dumping 'GPOS' table...
Dumping 'GSUB' table...
Dumping 'hmtx' table...
Dumping 'kern' table...
Dumping 'DSIG' table...
node index.js
Reading original font file ./original/OperatorMonoSSm-MediumItalic.ttx
Building ligature font file ./build/OperatorMonoSSmLig-MediumItalic.ttx name = default
Patching names
Patching charstrings
* less_exclam_hyphen_hyphen.liga
* equal_equal_equal.liga
* equal_equal_greater.liga
* equal_less_less.liga
* exclam_equal_equal.liga
* greater_equal_greater.liga
* greater_greater_equal.liga
* hyphen_hyphen_greater.liga
* less_equal_equal.liga
* less_equal_greater.liga
* less_equal_less.liga
* less_hyphen_greater.liga
* less_hyphen_hyphen.liga
* ampersand_ampersand.liga
* bar_bar.liga
* bar_greater.liga
* colon_equal.liga
* equal_equal.liga
* equal_greater.liga
* exclam_equal.liga
* greater_equal.liga
* hyphen_greater.liga
* hyphen_hyphen.liga
* less_bar.liga
* less_equal.liga
* less_hyphen.liga
* less_slash.liga
* plus_plus.liga
* question_question.liga
* slash_greater.liga
* underscore_underscore.liga
* ampersand.spacer
* bar.spacer
* colon.spacer
* equal.spacer
* exclam.spacer
* greater.spacer
* hyphen.spacer
* less.spacer
* LIG
* percent.alt
* plus.spacer
* question.spacer
* slash.spacer
* underscore.spacer
* uniE0A0
* uniE0B0
* uniE0B2
Patching glyphs
Patching hmtx
Writing ligature font file ./build/OperatorMonoSSmLig-MediumItalic.ttx
Done
ttx
Compiling "./build/OperatorMonoSSmLig-MediumItalic.ttx" to "./build/OperatorMonoSSmLig-MediumItalic.otf"...
Parsing 'GlyphOrder' table...
Parsing 'head' table...
Parsing 'hhea' table...
Parsing 'maxp' table...
Parsing 'OS/2' table...
Parsing 'name' table...
Parsing 'cmap' table...
Parsing 'post' table...
Parsing 'CFF ' table...
Parsing 'GPOS' table...
Parsing 'GSUB' table...
Parsing 'hmtx' table...
Parsing 'kern' table...
Parsing 'DSIG' table...
fonttools
Compiling features to './build/OperatorMonoSSmLig-MediumItalic.otf'
ERROR: The following glyph names are referenced but are missing from the glyph set:
 underscore.alt (first found at ./features/default.fea:142:20)

• Ubuntu 22.04
• Python 3.10.7
• Node 16.17.0
• Installed fonttools with all extras

[labs-dlugo]

The ligatures themselves not working under VsCode as well.

Fira Code's ligatures work.