WindowRef.getWidth/getHeight and ItemStackRef.isEmpty/getMaxDamage match methods of the classes they're mixed into, so the mixins can't implement them explicitly. With Mojang's names, Window.getWidth is also the framebuffer's width rather than the window's. They're now getWindowWidth/getWindowHeight and isEmptyStack/getMaxItemDamage (with getItemDamage to match). Co-Authored-By: Claude Opus 5.5 <[email protected]>