One to Many substitution

All of the documentation that I can find (glyphs, fontlab, microsoft, github…) all indicate that one can decompose a ligature with a “one to many” substitution like this:

sub ffl by f f l;

in a liga, dlig or clig feature

When I do this, the code compiles, there are no errors or flags but the substitution simply does not work… well it works in MS Word but not in Adobe illustrator or other apps that I’ve tested.
Yes, I did remember to turn on the liga and dlig features in Illustrator but no luck.

I’ve read that “one to many” substitutions are not supported everywhere but it seems that they are in the Adobe suite. Does anyone have any tips for me or any alternate methods to achieve this same result? Thanks!

IIRC Illustrator does not support one-to-many at all, and InDesign only in one of its composers.

But you probably don’t really need this substitution type for Latin.

Hello, Thank you.

Need? No. Want? Yes. I’m on a mission. It’s for ornamental purposes & I promise theres a good reason.

Is there an alternate method to achieve this result? It seems that indic scripts & other scripts include single glyphs which are substituted by multiple glyphs with anchor-based positioning like components. Thats exactly what I need but I need to do it in a feature and I need it to work for Latin.

Any help would be greatly appreciated.

As I said, try the composers.

Otherwise ask Adobe to improve OpenType support in their apps. I believe they have a website for feature requests.

Illustrator has the composer that supports one-to-many substitutions, too. It is just better hidden. So this should work in Illustrator.
But as it is difficult to explain to a customer of your font how to get it work, it can’t be used if the font has to be use in adobe apps.