Red has been changing things around, which may have led to this error, but it seems to be fixed now. I do apologise, but when making changes to the site, anything can happen. Thanks for telling us, especially me, as I use the Quick Reply box in the bottom left-hand corner far more than the quote button.
Anyway, normal service seems back. There have been a few problems, but they seem short-lived, I think. If you spot anything else, please let us know. Also, we are always open to suggestions for improvements and changes. ;-)