When diffing https://github.com/bettergui/BeVietnam, it crashes when trying to dump the mark records. I've solved this issue by skipping mark combos if they only contain base glyphs.
The OT feature dumpers are a bit of a mess. I'm making fairly good progress on fontTools.otlLib.unbuild which should tidy up this code significantly.
When diffing https://github.com/bettergui/BeVietnam, it crashes when trying to dump the mark records. I've solved this issue by skipping mark combos if they only contain base glyphs.
The OT feature dumpers are a bit of a mess. I'm making fairly good progress on fontTools.otlLib.unbuild which should tidy up this code significantly.