@Andrew what is the :key used for?
It’s a way for Vue to keep track of the “nodes” that it creates with v-for. Can read more on list rendering and :key here.
It’s not mandatory but highly recommended by Vue.
the key needs to reference a model value? For instance, it can be “anything” as long as the key:value pair is present?
It should at least be unique. If there’s no unique value then the list is probably relatively simple and may not need a :key.