most or should i rather say all of fridge nowadays has "auto defrost" systems that lets you forget about drain pans. Initially, most would think that it is a neat design in which the heated freon pipe passes over the drainpan and evaporates the defrosted liquid/water.

unfortunately, thats a very nasty design, its like a ticking timebomb that forces you to purchase a new fridge every <10 yrs

the copper freon pipe would go on a cycle of heating up, getting exposed to water, dries up and repeates the cycle over and over. Take note that metal + water + air = rust

and these rust can cause freon leaks and makes your fridge useless, also, these fixes costs like MF(almost half the price of a bnew fridge)

I would advise DIYing a flexible tube on its drain hole and routing it on a condensate pump, I would not advise routing it to a sewer line because nasty sewer gas will get in the fridge.