This! This is one of those old timey things you hear about and think is bs, but actually works. I don't even remove the berries from the packet because I am lazy.

I fill a tupperware with apple cider vinegar and water, measured with my heart, and dunk the berries in it, container and all and let sit while I unpack groceries. Then I give them a shake to remove as much vinegar water as I can and toss them in the fridge. I don't rinse them, no they don't taste like vinegar.

A couple years back strawberries were $1 a punnet here and I tested this - the ones dunked in vinegar lasted a week or more with no soft spots, the ones without lasted just a few days before developing soft spots.

So yeah. Dunk them shits in vinegar. It works!