Using Import Master gives "Stems can't be zero" at imported master location

Glyphs
1

Hello, I am using Import Master. I’ve got through most of the headaches (including using alternate layers), but there is one thing that I can’t find a solution to: trying to export from the file works, except for the instances at the location of the imported masters, for the following reason:

Stems can’t be zero.
Please fix this in the Font Info

I have set up (compatible) stems in all masters. Same names, same amount.

Any reason for this?

2

Okay, it looks like the stems for imported masters are set to 0, regardless of the stem settings in those masters.

Checking like this (for an instance that is at the location of an imported master):

m = Font.instances[-1].interpolatedFont.masters[0]
print(m.stems)

Gives me:

(
	0.0,
	0.0,
	0.0,
	0.0
)

Testing with an instance close to that location gives:

(
	2.0,
	1.0,
	3.0,
	2.0
)

Which shows that the stems are interpolated between the actual stems of the font’s masters and stems with have a value of 0 for the imported masters.

3

Could you send me a test font.