There are many Mastodon instances with which your home instance federates but which you might not want to see in your timelines. Fortunately, you can hide all toots from a given instance.
1) In your home instance's web interface, open the account of a user on the server you wish to hide.
2) At the bottom of their profile, next to their follower/following stats, is a "..." menu. Click that.
3) At the bottom of the new context menu, click "Hide everything from <instance>".
@Yarideki It will block /everything/, including the people you already follow, so be careful.
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