I previously replaced the cover on the light under the sink, but it got knocked off again, so I decided to replace the whole light fixture this time, figuring that the clips that hold the cover on may be weak.

The light is available from Tiffin’s online parts store, part number 5032143 “Light Wardrobe Brown LED”:

Rather than using the wires that came with the light, I simply unplugged the existing wires from the old light, and plugged in to the new one. But the light didn’t work; it turned out that I needed to reverse the wires; so I guess the original was hooked up differently:

But all good now:

An easy fix.