Variable font: Instance 'Regular' often replaced by other instances

Glyphs
1

Variable font with 3 masters
Axes: weight only
9 standard instances: Thin, ExtraLight, Light, Regular, Medium, SemiBold, Bold, ExtraBold, Black
Every time I export it as Variable font, in TextEdit I see Regular weight as Thin weight, so practically there are two Thins with different names.

Which is my mistake?

2

I would need to know more about the setup. Can you send me the file?

3

Sure

4

@GeorgSeifert Could you please report afterwards how and what ? I have a similar issue. After making a VAR with fontmake The lightest Roman weight is default. I would like it to be the Regular.