The "psychedelic colours" are a really unfortunate consequence of the fact that Outlook is still incapable of producing sanely quoted text after about 20 years.

The "psychedelic colours" are a really unfortunate consequence of the fact that Outlook is still incapable of producing sanely quoted text after about 20 years. It's extremely frustrating considering that most email clients did it right back then. Even Gmail manages to get it mostly right most of the time.