Fetching remote communities for first time is very slow

[Nutomic]

This is because it also fetches the community outbox, which includes the last 20 posts. For each post, if it has a link, the site metadata is fetched. This is done serially for one post after another, with a timeout of 10s. So in the worst case, fetching link metadata alone can take 20 * 10 = 3m 20s for a single community.