PE script includes a function for setting the language tags on an OpenType feature. FontForge's documentation says this function is called LookupSetFeatureList, and the equivalent Python function is called that, but what's actually implemented in FontForge's PE script and inherited by FontAnvil is a function called just SetFeatureList. Reported by Itai Shaked on the fontforge-users mailing list:
Should probably be addressed by adding an alias to the existing function. However, using this function requires using nested arrays, which in general don't work in FontForge PE script:
Common use of (Lookup)SetFeatureList may be a case that doesn't crash, but the crash ought to be fixed anyway, and FontForge would probably welcome a backport of that fix.
mskala 
Tsukurimashou Font Family and IDSgrep
PE script includes a function for setting the language tags on an OpenType feature. FontForge's documentation says this function is called LookupSetFeatureList, and the equivalent Python function is called that, but what's actually implemented in FontForge's PE script and inherited by FontAnvil is a function called just SetFeatureList. Reported by Itai Shaked on the fontforge-users mailing list:
Should probably be addressed by adding an alias to the existing function. However, using this function requires using nested arrays, which in general don't work in FontForge PE script:
Common use of (Lookup)SetFeatureList may be a case that doesn't crash, but the crash ought to be fixed anyway, and FontForge would probably welcome a backport of that fix.