In the world of Hai:
I posted a link, clicked to follow and then clicked back to come back to the previous page. It prompted me about content form resubmission, but I honestly wasn't paying attention, so it posted again. Not sure what can be done about that, but if going out and back will always come up with a content form resubmission dialogue, I anticipate a lot of double-posts.
OK, thanks for the bug report!