'Query-selecting elements from multiple elements, efficiently

Say you have an array of elements and you want to get all the <p> belonging to the elements in the array.
I can see two possibilities:

  1. Run Element.querySelectorAll() on each element of the array and then concatenate all the various NodeLists of <p>

  2. Run a single Document.querySelectorAll() and then filter out all <p> not belonging to any of the elements in the array

I don't have such a deep knowledge on the mechanics of query selectors to be able to make a thoughtful decision.

What is most performant, to run more queries on smaller elements or to run fewer queries on bigger elements (actually only one on the biggest of them all)?


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