Or something like that. I've noticed it several times now, but there's been a time or two when I didn't.
I'll see if I can explain this the best I can: You type up a post, hit submit and get this message that states something to the effect of "there's been a post in this thread something something something" and unless you catch it and hit submit again your post doesn't make it.
I'll try to paste it in here the next time it happens.
I would like to request that this be disabled, if possible. Especially as the season draws near and the posting becomes much more frequent. Imagine typing up a rather lengthy post only to have it be lost due to missing that little warning...that would suck!