EDIT: This glitch has been fixed.
No posts affected by the glitch were deleted, they were only hidden from view.
As some of you may be aware, a new update to the site went through a couple of days ago.
Unfortunately, due to a glitch in this update, nested posts (which you get when you reply to an individual post) that themselves have responses are being automatically deleted when you refresh the page.
As you can imagine, this is very very not good.
Because of this, we ask that for the time being, you DO NOT REPLY TO INDIVIDUAL POSTS. Instead, please use the 'Add Comment' button at the bottom of the page - that way, we can guarantee that your post will not be lost.
(We also ask that you don't try creating posts just to try this out - because SOMEONE will want to)
We apologize for the inconvenience that this may cause, and assure you that we're trying to get this problem fixed as soon as we possibly can. We'll let you know of any further developments with this.