Additional Master using the brace trick on CPAL/COLR Color Fonts

Dear Glyphs community,
Is it possible to add additional masters using brace trick to color layers. This is a screenshot of my attempt, it illustrate what I want to achieve.
I want to add 2 additional masters using brace trick to my variable color fonts, one for {30}, one for {70}. This setting does export a variable color font but the color 1 layer disappears after axis value reaches 30

Brace trick ref:

Never tried this. But what should work is that you do the brace layer in a different glyph, and add that one as a component on the color layer.

Thank you mekkablue!
I will try that method!

Can I make this into a feature request? Adding brace trick to color layers. when i am experimenting with it, the preview already look correct, it is just the exported fonts that has issue. This feature is super helpful of people making variable color fonts.