I successfully compiled Marlin 2.1.x bugfix for my Arduino DUE-based printer, but to get my (ancient) UltimakerController display working, I needed to use the Arduino LiquidCrystal library (1.0.7) versus the one that PlatformIO finds by default via LDF (1.5.1). I did not debug why LiquidCrystal 1.5.1 didn't work, but I suspect it might be the "fastIO" optimizations that help AVR-based Arduinos write I/O faster. I'm pretty sure these optimizations are not necessary for DUE and perhaps they're causing some kind of problem. Does anyone know if there's a (proper) way to disable fastIO optimization in LiquidCrystal 1.5.1 when building via Autobuild Marlin+PlatformIO?
