Hi Colin,
Two tips to save you loosing your hard work.
1. Just before you hit the submit button, highlight all your text, then press [CTRL] and [C] - this copies all of your typing into the clipboard - then if the site chokes - you can just use paste [Shift] and [Insert] to recover all your text
2. You may want to use the free Windows notepad to enter your text - then use the copy and paste trick to enter the text into the PC message
Both of these work with Spell Checkers
Robert