block

 Block  is a feature on many silos that provides the ability for one user to "block" or prevent interactions from another user.

Blocking is similar in some ways to muting someone, but beyond not seeing content from that person:

Blocking someone typically means:
 * they cannot follow you nor view your profile while logged in
 * they cannot favorite, repost, or reply to your posts
 * you don't see content from them in *any* context on the silo

Good implementations of block (e.g. Flickr's implementation of block)
 * remove any of your content from that person's collections (e.g. favorites collection)
 * remove any old comments from them on anything of yours

Brainstorming
Building blocks in progress towards enabling indieweb block features:
 * http://microformats.org/wiki/block-list
 * http://microformats.org/wiki/block-list-brainstorming
 * Private posts and public post upgrading to enable private lists: private posts

Modest minimal proposal:
 * use-cases:
 * block a specific abusive/noisy comment (like a delete)
 * block a specific abusive/noisy user
 * private "because" field to keep track of why (perhaps when?) you blocked someone (per request on Twitter)
 * format: a set of URLs
 * behavior: block any URLs that are prefix-matched from that set. E.g. if "abuser.example.com" is in the set, then "abuser.example.com/?post=123" would be blocked. Use-cases thus:
 * block a specific comment by canonical permalink
 * block a specific user by their homepage or silo profile URL.

Implementation discussions:
 * Bridgy: https://github.com/snarfed/bridgy/issues/473
 * A WebMention Endpoint: https://github.com/voxpelli/webpage-webmentions/issues/31

Mastodon
(stub)

Mastodon has a block feature that allows you to block an individual user (no matter where they are hosted), or an entire Mastodon site ("instance") and all its users.

Examples needed.

Screenshots needed.

Facebook
Facebook has a block feature. From their inline help on facebook.com (partially documented in How Do I Block Someone):

You can block someone to unfriend them and prevent them from starting conversations with you or seeing things you post on your Timeline. People you block can still see and comment on stuff you share in groups, apps and other shared places.

Flickr
Flickr's block features is viewed as the current best-of-breed and most well designed/thorough block feature.

For details on what Flickr means by block, see:

https://www.flickr.com/help/contacts/?search=blocking#96

Twitter
Twitter has supported a "block" feature since 2007 April (or possibly earlier).

Twitter's "block" feature is widely viewed as insufficient, and has been through a number of iterations, one of which was no more than a renamed "mute" (which they later actually released as a "mute" feature itself, since that by itself was useful for other use-cases).

Description from Blocking Users On Twitter:

“Blocked users cannot:


 * Add your Twitter account to their lists.
 * Have their @replies or mentions show in your mentions tab (although these Tweets may still appear in search).
 * Follow you.
 * See your profile picture on their profile page or in their timeline.
 * Tag you in a photo.”

Note that this user-facing documentation does not mention the caveat about retweets detailed on the /post/blocks/create API documentation (emphasis ours):

“…the blocked user will not show in the authenticating users mentions or timeline (unless retweeted by another user).”

Twitter also has a support document covering Online Abuse, recommending blocking offending users.

Twitter fails to hide blocked comments
Twitter fails to actually remove blocked users from your permalinks. All it does is hide them only from you.

Twitter shows blocked users' comments on your tweet permalinks to all other users (and the general public for public accounts).

Here is an example tweet permalink with a comments removed from a blocked user, shown only to the blocker (original poster)



Yet here is how that same tweet permalink looks to others or the general public:



Note the semi-nonsensical comments from @caca_dhavid (blocked user).

More examples (with one or more blocked abusive comments, publicly visible)
 * https://twitter.com/t/status/826255614586322953
 * https://twitter.com/t/status/825973155630051328

Importing Block Lists
Twitter allows you to import a csv file with a list of accounts to block.



External Tools

 * http://www.theblockbot.com/sign_up/connect.php
 * Example of a shared block list targeting advertisers: https://www.theblockbot.com/show-blocks/OLntUGaCZE_4mevqfUrMvBsriyyBdhaFoFrvjiG4
 * https://web.archive.org/web/20191228224131/https://blocktogether.org/
 * Shutdown as of January 2021: https://blocktogether.org/