I was writing OpenType code and wrote
languagesystem comment dflt;. It means the algorithm merely looks for whatever mention of
script and the following word. This is annoying, and could cause more errors in the future.
Experimenting further, I added a glyph named “script” to the font and used it in a feature code. The algorithm highlighted that glyph name and gave me a syntax error (happens with “language” too). It also generates a Languagesystem by the same logic as above. At this point, you can crash the app by editing the feature code in a certain way.
Could the logic be more sensitive to the actual OpenType syntax?