[sigsergv]

Funny thing: I still don't know what [-] means, there are no tooltips or any other hints so I prefer not to click it.

[realusername]

It's just a simple collapse thread feature.

[derefr]

Not so simple; it persists the collapses somehow (I think server side attached to your account rather than your session.) That’s a lot more complexity than the equivalent Reddit feature, for a change.

[MrGilbert]

Hm... I always thought it has to do with the comments that get slowly grayed out? E.g., for me that was basically a "downvote".

[mjlee]

There is a downvote button, but you need some minimum karma for it to be available to you.

I can understand why it might be confusing if there's no downvote arrow visible!

[MrGilbert]

Yeah, that some kind of UX pardigm - don't hide the control. Disable it, and explain the user why he cannot use it at the moment.

On the other hand, though, I can now simply collapse huge branches without downvoting anyone, so thanks for the clarification! :)

[RandomInteger4]

[-] just hides that branch of the comment tree so that you can ignore it if you want to focus on reading other branches.

[echelon]

You've been here since 2012! :)

That's really interesting.