We had one of the plastic
nubs to break off from our small Whirlpool
refrigerator.
I didn't think super glue
or epoxy would be strong enough, so I found a dull drill bit that was
the right diameter and installed it far enough in so it sticks out like
the old nub did.
The middle section of the
door is no doubt filled with some kind of styrofoam, which is why I
drilled a smaller pilot hole first to help get the bit positioned as
straight as possible.
It works fine and feels like
a long lasting solution.