If we queue N UUIDs [1, 2, ..., N], we’ll send a request to fetch all of
them. If we queue those same N UUIDs again, we’ll stop processing after
the first one, without sending any fetch request.
We’ll start processing again the next time `process()` is called. This
could happen in response to network availability changing, or it could
happen in response to scheduling the N+1’th UUID. (Though, we won’t
necessarily fetch the N+1’th UUID in this case -- we’ll fetch the 2nd.)
These cached results also expire after a few minutes or a few hours,
depending on the most recent result. Therefore, this fetcher may behave
somewhat erratically, where it fetches profiles, stops for a few
minutes, then starts fetching profiles again.
f2afe8d45b