I am working on a font with stroke outline as source. The export in all formats works pretty good, the outlines expand and merge well. The problem comes from the color font version, and I saw in the OTF and TTF file that the “black” layer was not merged, the outline is expanded only. Which I presume is at the origin of some overlap issues (depending on the software and version of course).
Composite glyph in source (the last black layer only contains the letter):
What the stroke component looks like:
So you can already imagine that with this loop, there will be an issue.
How it looks in the binary: the first layer is merged properly, but not the “black” layer only containing the letter.
So I could fix that by expanding the outline and merging myself in the sources, but since it does look like a bug and I would like to avoid expanding the outlines, I report 