The manual for my dishwasher says to refill salt just before running a wash cycle, because if any grains of salt spill onto the stainless steel interior it will corrode. If it runs right away, no issue because the salt is quickly dissolved, diluted, and flushed.
So then I realized when I cook pasta I heavily salt the water (following the advice that pasta water should taste as salty as the ocean). But what happens when I leave that highly salty brine in a pot, sometimes for a couple days to reuse it? Does that risk corroding the pots?
I can't imagine it's particularly food safe to leave your starchy pasta water out for a few days and then reuse it.
In any case it's far less salty than what could potentially happen in the dishwasher with a relatively large amount of the decalcifying salt and a couple drops of water.
Worst case you can polish and re-passivate your stainless steel cookware, but it shouldn't come to that.
I haven’t tested a few days of non-use. It’s usually if I happen to make pasta two days in a row, and (more rare) three days in a row (where it still boils daily).