I've been wondering what these numbers represent in React Query Devtools. I searched online, but I can't find it's meaning.
I thought cache ID. But I see duplicates. The total number of rows with the same color always equals the numbers in parenthesis in the same colored headers. But the actual numbers, I don't know what it means.
I was wondering about this myself. It turns out that it indicates the number of observers.
Here is discussion on github that talks about it.