Can people still see FB message with out telling me they've seen it?

[vintageowl]

Yep! Ok, so this is how you do it:
1. If they are online, your message will pop up on a little open chat window. They can read that message from there, and as long as they don't touch the window, it will remain unseen.

It's really irritating just leaving it though, as it will keep flashing if you don't click on it or you don't close it, So...

2. You can click on the 'messages' tab on the left hand corner and it'll come up with all messages in the inbox. If you hover your mouse over the message, you'll come across a little circle on the right. If you click that, you can mark it as unseen!

Hope that helps! xx