I'm curious if this happens to you:
You are having a private chat with another member and they receive a duplicate message of one you have sent previously to them during that same chat session. The super odd thing is, only they will see it on their screen. If it is my message that is getting duped, I will not even see it.
It is not user error and it is not browser specific. But it is annoying. I typed a member's name wrong once and she jokingly corrected me. Minutes later the system duped that message and she made a comment like, "I hope you don't spell my name wrong again!" Luckily, I am the kind of person to get to the bottom of things like that.
Another time, I member and I set up a time to chat, and she knew I was coming home from a BBQ to make it happen. The dupes were in full force and she ended up accusing me of being drunk! haha. (I hardly even drink at all.) She wouldn't listen to my reasoning and she stopped communicating with me after that. No big loss, but I'd rather not deal with this difficulty.
So . . . is this happening to you (maybe even without your knowledge?)