Problems reading the fvar table

We’re reading variable fonts with opentype.js and are running into a strange problem with the fvar table.
As you can see in this screenshot, it seems to read all of the instances except the Regular one. It is definitely in there, and is being read by multiple online test tools, so we can’t really figure this out. Do you have any idea of why this is happening or what the solution is?

Perhaps it is because it thinks the word regular is elidable. But it should only be deleted in combination with other particles.

But we cannot really tell unless you publish your code.