INVESTIGATE: Support minimal "replying to..." pseudo-quotes in replies without harming privacy

[neatchee]

Pitch

Multiple theoretical components to this feature:

• Small 'quote-like' box at the top or bottom a reply
• Opt-in/out options for the entire feature, as well as individually for 'show first N characters of post' and 'show username'
  • "Replying to : This is the first 45 characters of the post bei..."
  • This is a setting for the user being quoted NOT the user doing the quoting
• Default 'on' for local users but hard-coded 'off' for remote accounts; never quote a remote account that can't opt in/out
• Sanitize content before quoting; do not include mentions, media, links, etc; only simple text
• Other privacy focused elements? This needs to be extremely hardened if we're going to do it

Motivation

With the ability to push replies into public timelines, usefulness is diminished when replies show no context from the post being replied to. It'd be great to find a non-invasive/privacy-breaking way to allow replies to include very limited context of the post being replied to

[deanveloper]

Is it really a privacy concern to show the post that's being replied to? The replied post can still be seen if you click on the post even if the "replying to" setting is disabled, right?

[neatchee]

This is more about friction than prevention. It's not that people CAN'T do it, it's that they're less likely to when there is more effort required.

[deanveloper]

I guess my question is, is it really a privacy concern? What would be the benefit of the "opt-out" of being shown in replies? I haven't given this too much thought though so I could be missing something. Is it like, the person being replied to doesn't know their post is being shared with our instance since it wasn't boosted?

My main concern with only having the preview sometimes show is that it'll probably be very confusing that some replies will show the original post while others won't.

[neatchee]

So, I think this should behave vaguely like RTs on birdsite in terms of having it be something you enable at time of post, right? Like, "I want this reply to include a quote of what I'm replying to, but only the beginning of it" lol. This would likely be a local-only feature unless it gets adopted upstream.

Re: privacy, that's part of it. Imagine you have a problem with a stalker or harasser. Privacy settings currently allow you to strictly control who is even aware your account exists. If the preview can't be prevented from exposing information to would-be attackers then it's a no-go. Someone who wants to whitelist their post visibility should not have to worry about one of those whitelisted people making a reproduction of some of post contents in their own, more visible posts.

The best approach may be to design it so that you can't see the preview for a post that you don't also have visibility on, independent of the visibility of the reply containing the preview

[deanveloper]

Oh yeah that'd be an issue for sure. A permissions check is definitely required of course.

I think adding a "replying to..." above the post with just the user would be very nice, the Megalodon Android app has it (and I believe the official Mastodon Android app as well)

Maybe the following rules would be good:

1. If the reader can't read the OP's post, hide the reply indicator entirely. From what I can tell, there's only two cases where this would even be possible.
   1. Either the OP or reader is blocked by each other.
   2. The OP set their post to "Followers Only" and the reader does not follow the OP.
   3. I need to take a deeper dive into how these privacy settings work, since ideally the reply shouldn't even show up in the reader's timeline in these situations.
2. If the OP's post is set to Public, I think we can show a reply indicator since that means they've opted into discovery.
3. If the OP's post is set to Unlisted, we should show a reply indicator with the user's display name, but hide the content of the post. I think this should be a good way to prevent confusion while still preserving some privacy.

I think later we can add a user-setting to opt-in for post content being shown in reply indicators if your post is unlisted. Might even be good to add this to server-to-server communication if we want to merge this into glitch-soc.

And of course, we should add a local setting to disable this feature for people who just don't like the look 😄

related (not quite the same thing, but related) - mastodon#19690