Variable font issue: Weight "Thin" exported as "Regular"

I am working on a variable font.
I have 2 Masters and 9 instances (weights: 100 - 900).
The instances are named: Thin, UltraLight, Light, Regular, Medium, SemiBold, Bold, ExtraBold and Black.
So, Thin = 100 and Regular = 400.

But when I export it as a Variable font (___GX.ttf) and install it, the default Font Book installer shows two instances named Regular and no instance named Thin (Screenshot attached).
Interestingly, one of the “Regular” instances has the glyphs that weigh 100 (a.k.a. Thin) and the other one is just Regular (weight: 400).


After installing it, on my browser (Chrome), font-weight: 400 renders the Thin (weight 100) instance of the font.
But the property font-variation-settings: 'wght' 100; works fine. Increasing the weight from 100 to 900 renders the absolutely correct weights.

Plz help me with the issue here. How do I fix this?


  • I tried renaming the instances, but the issue persists.


  • Exporting the font individually by weights (9 files) works fine.
  • On Firefox, both properties font-weight: 100; and font-variation-settings: 'wght' 100; render the boldest instance of the font. I am safely guessing, each browser has a different way of handling a buggy variable font.
    (Fixing the duplicate and mis-matched naming of the instances should fix the browser issues).

Which version of Glyphs?
Do you have axis location parameters in Font Info > Masters?

I’m on v2.6.4.

Here are my axis parameters.
For Weight 100:

For Weight 900:

No params in Stems.

Try the latest beta please. Go to Glyphs > Preferences > Updates, activate both checkboxes and press the Update button.

Did it. Now on 2.6.5.
But, the issue persists.

Can you please send me the .glyphs file to support (at) (this website without www). I will have a look.

Sent the email with the glyphs file attached. :+1:

Cannot reproduce. It shows as Thin for me in Samsa:


Some thoughts:

  • Are you sure you are using the latest betas? 1330 or 1338 should be the build number.
  • Control the default fallback style name with variableStyleName, typically Roman or Italic. It didn’t make a difference for the styles menu though.

I’m not sure what Samsa is.
Were you able to try it on Mac’s default Font Book?

I’m on the latest build: Version 2.6.5 (1338).

I also sent you a blank new glyphs file (no characters). That also has the same issue. Were you able to check that too?


I used that file and inserted plain rectangles to see if the interpolation is at the right spots.

The font is fine. If Fontbook does not display it properly, that is more like a bug. Perhaps it always displays the first instance as regular…?

Samsa is here:

What does the font display for you on the Mac when you try to install it? Just basic installation on a Macbook. Without checking on plugins.
Because even if the variable font looks fine on Samsa or any other font inspector, but it has an issue when being installed on a Mac, that could be a crucial bug.

I tried to install another variable font (Work Sans) and that was fine. It did not have this issue.


I did find a mistake. Regular was not declared elidable for the wght axis. What you can do is add two parameters in your Regular instance: both Elidable STAT Axis Value Name, once with wght and once with ital as value.

See if that fixes your problem.

I did try adding Elidable STAT Axis Value Name custom param, once with wght and once with ital as value.
But it did not work.

I read up more on Elidable STAT Axis Value Name on the tutorial and I wanted to clear up that I do not have multiple widths. I only have multiple weight instances.

I was also able to try the “Manrope” font glyphs and was able to recreate the same issue.
The .glyphs file for that is available here:

It would be extremely helpful if you or someone can try to recreate the issue. The steps are very simple and basic.
Just Export the glyphs file as a Variable Font and open the exported variable font file (GX.ttf) with FontBook (Mac’s inbuilt default installer).


I did and I found the issue already. Now I am trying to find a solution. It looks I will not be able to spare you from editing your file with ttx.

This entries in STAT has a wrong flag set:

      <AxisValue index="3" Format="1">
        <AxisIndex value="0"/>
        <Flags value="0"/> <!-- SHOULD BE 2 -->
        <ValueNameID value="260"/>  <!-- Regular, value can be something else -->
        <Value value="400.0"/>

Flags should be 2, but is 0. That is what the custom parameter should take care of, but it seems like it didn’t. So until we can fix it in Glyphs, you can use ttx or OTMaster to edit the STAT table yourself.

Thank you. :+1:
I am glad the root cause has been found.
I do not have OTMaster. I can wait for a new release of GlyphApp’s. :slight_smile:
Any idea what version/patch will it be on?

We just tested again. Adding the Elidable STAT Axis Value Name helps, but macOS seems to require a variableStyleName as well. Add a custom parameter with that name and the value Roman to Font Info > Font:


Then Font Book takes it as expected.


Confirmed to work with in 1338.

:partying_face: That worked!

It exports the font with the variableStyleName value in the file name.
But, the issue is fixed.

I read about variableStyleName on the site and from what I can tell, the value doesn’t need to be one of a specific list of allowed values. The value can be “Roman” or “Display” or “Sans”, correct?

Either-way, I can always rename the exported file.



Need to continue this thread. Found a related issue.

When exporting as otf/ttf (individuals weights), browser render for weights 200 and 300 is the same.
That is: font-weight: 200 and font-weight: 300 display the exact same glyph set.

Tried it on both: Chrome and Firefox.

I have sent the glyphs file to support (at) (this website without www).