Prevent users from accidentally clearing their replies

I had, at one point, typed out a whole reply to a thread, and wanted to refer to something a couple pages back, so I Ctrl+left clicked to open the previous page in a new tab. Much to my chagrin, it moved back a page in the current tab, and cleared my post without asking. After that, I gave up posting. Adding some sort of draft feature, and the standard "Are you sure you want to leave the page?" message would be good, in addition to working on that issue where it didn't open in a new tab in Mozilla. Even if one of the first two were implemented, that would at least hold off a lot of problems.