Yeah, that will happen if you take too long typing the reply and your session times out. Especially if you visit the site at about the same time everyday, and the 24 hour cookie that you get when you click through ADT's adult content warning screen timed out while you were typing the reply. When you get the blank preview screen, your best bet is to copy the message to your clipboard, backtrack with your browser, and then paste your message into a new, fresh Post New Reply text box.

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