I bought some Harrier soft flasks recently and designed a dryer around them.

The 4 legs can be removed and stowed inside with the lid on top.

The lid is made to a fairly tight tolerance so you may want to sand slightly around the edge so that the layer lines don't lock the lid in place.

Use the buck .stl file as a mesh modifier in prusa and remove top and bottom layers and perimeters. Then choose the type of infill you want. I chose honeycomb to let the water drain out.