Alternate Characters Issue in Illustrator

I’m having an issue with some alternate characters that I have set up in my typeface. I have a number of alternate characters set up (sometimes more than one alternate per character) using the following naming convention: A.alt.01, M.alt.02 etc.

When I load the font into illustrator and use the special characters, everything looks fine. But if I select the entire word and try to change its weight, the regular characters change weight, but the special characters remain in their previously assigned weight. So I write out the word ‘hamburger’ in bold, change the ‘R’ to a special character, then change the weight of the entire word to light, and everything changes to light except for the ‘R’, which remains bold.

I’m not experiencing this issue in InDesign.

I’ve tried experimenting with the naming logic: dropping the second period in the name to A.alt01, M.alt02 etc. but still having the same issue…

Any thoughts on what is causing this?

How do you do that? Are you using the Adobe Fonts folder?

You need to have some opentype features to be able to properly use the alternate characters.

Rename them to A.ss01, M.ss01. Then go to Font Info > Features and press the Update button.