[pfefferle]

Fixes #3910

Proposed changes:

• Replies to remote posts from followed accounts are stored as comments on ap_post. The admin already hides them, but the comments feed and the comment widgets did not. Now they skip them too.
• Comment::comment_feed_where() leaves out comments on the post types from hide_for(). It uses a subquery on comment_post_ID, because the feed of a single post has no posts join. It also applies with type=all.
• A new widget_comments_args callback leaves out the same post types in the Recent Comments widget and the Latest Comments block, unless the caller sets its own post_type.
• Other front-end comment queries stay as they are, because the inbox and cron lookups have to find reader replies.

Other information:

• Have you written new tests for your changes, if applicable?

Testing instructions:

• Follow a Mastodon account from your ActivityPub profile.
• Reply to one of its posts on Mastodon, or let someone else reply.
• Open /comments/feed: the reply is not listed.
• Add a Latest Comments block to a page: the reply is not listed there either.

Changelog entry

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Changelog Entry Details

Significance

• Patch
• Minor
• Major

Type

• Added - for new features
• Changed - for changes in existing functionality
• Deprecated - for soon-to-be removed features
• Removed - for now removed features
• Fixed - for any bug fixes
• Security - in case of vulnerabilities

Message

Replies to posts from accounts you follow no longer show up in your comments feed and comment widgets.

The entry is already part of the branch.