Feature Request: 'Filter' custom parameter for masters

I think it’d be useful to be able to give masters the ‘Filter’ custom parameter for use with exporting variable fonts.

For example I currently use this script to export my variable fonts with all components decomposed (to fix the spacing issues on mac) but having it as a filter would be much simpler workflow-wise.

I’m thinking about a place where to put variable font settings like this. Masters are not quite the right place, think.

Are there any updates on this? To avoid confusion with the normal Filter parameter perhaps it could be named something like “Variable Font Filter” to provide a separation of concerns?