FCKEditor FireFox bug

Hi,
just try in FireFox to do the following: Ctrl-A, backspace or del, (or just remove all text using backspace) and then press del again. You will see all JS code inside of the editor. Or this way: start a new paragraph, type some text and then start to press del... Some may say: why press del being in the end of a text. Yes it doesn't make sense... but I am terrified to think about some careless user of mine who may encounter it.... looks too bad...
Great thing otherwise