I don't know if anyone else has experienced this, but if your private message is too long, it will get cut off. Also, I would say copy and paste your private message to another document before sending, however, if you copy something while at a website, that website may be able to see the content in your clipboard, which is the temporary holding area where your copy or cut information is stored. However, if you don't mind that with your private messages, then doing that shouldn't be a problem.
And the other problem that I noticed is that in both sent and received private message, a forward slash(/) is put in front of quotation marks(") and apostrophes(').