Jello is sold ready to eat or in powder form and is found in flavours and colours.
Jell-O is a registered trademark of Kraft Foods for varieties of gelatin desserts, including fruit gels, puddings and no-bake cream pies.
It contains powdered gelatin and flavourings, including sutar or artificial sweetners.
It is dissolved in hot water then chilled so it is allowed to set. (source)
So can rabbits eat jello at all?
Unfortunately they cant eat it as it is too full of additives and sugar for rabbits to eat.
It will hurt their tummies if it is eaten purposely.
So it is a food to keep away from bunnies.