When I add a ligated glyph, I need to manually go to the Features panel of Font Info and click the circular “rebuild” button on my ccmp features. Similarly, if I remove that ligated glyph, I have to go and rebuild the features again or else the font won’t export.
Wouldn’t it be better to do that automatically, perhaps on export? Certainly if I remove the ligated glyph there is no reason why it should stay in the features table. It can be removed from the features immediately. And it might be helpful to automatically rebuild the features when a glyph is added too.
Another part to this: Is there are reason why the operations of “update” and “compile” are separate? Would you ever want to compile some features without updating the ones that should be automatically updated? Would you ever want to update but not compile?