Preheat Fluorescent Fridge Lighting Unit

Here is a cool find at one of my local Winn-Dixie stores. This is in a small corner section of the fridges in the produce section. Notice the starters...preheat! Interestingly, one side uses y-slot sockets while the other side has donut-slot sockets. Must be tricky to insert the lamps LOL! The fixture is very short, I think it might use F13T8 lamps. This is currently unused, and the rest of the fridges have been retrofitted with LED bars (not tubes). They too still have the old fluorescent sockets in place.