As a complete beginner, when I first started using Glyphs App I had to familiarise myself with lots of new terms, and one of those was interpolation and the concept of Masters.
Forgive me if there are similar features which allow this that I’m not aware of, but I wanted to suggest a way of previewing interpolated fonts that are generated when export occurs.
Where the Masters are currently displayed in the UI, if there was a way of viewing the weights that would be generated upon export, it would be really helpful to check for visual issues.
I’ve quickly mocked up how it might look to a user :-
Maybe even one day it could allow you to edit individual glyphs from instances to fix specific issues? (without having to create an entire new master)
Anyway, just throwing it out there - Glyphs is already an amazing product.