Fabric port is just an side project and it wasn't part of the main pipeline (so contributions are welcomed)
Right now the alpha port carries next issues:

• Displays doesn't emit light
• Displays cannot connect redstone
• Wrong push reaction (broken is the right one)
• Missing rotate method (might no affect)
• Missing rendering skip for BE Renderer (impl by forge)
• GuiSliders got stick in the Mouse (Caused by CreativeCore)

porting is done