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The hardest part of a grocery list is getting things onto it. The person who used the last of the milk knows it's gone. The person at the store doesn't. Here's a printable list for the fridge, and a way to make it a shared list on everyone's phone.
The free library has an automation that opens your store list when you arrive at the store. In the Automation Kit, the dinners you pick put their own ingredients on that list.