My 16mo daughter likes to repeatedly press the buttons on the dishwasher turning it on and off. LG in their infinite wisdom decided to build the dishwasher to play a tune when you turn it on so it is irresistible to my daughter.
This cover slots over the top when the dishwasher is open and then once it is closed it locks in place.
I printed this with 100% infill on transparent PLA from HobbyKing. 225/60C works for me with this filament on my Ender 3.
Turn it 180 degrees in your slicer to print without supports or rafts.
UPDATE: Thinned out the top and lip so the dishwasher can run while the cover is on. I was a little worried that although it clicks in fine, it sticks out by a mm or 2.