One thing that can be challenging about new subscription based software like Office 365 is that new features get rolled out and you don't even know it. There are places you can look but most of us don't check it out. Sometimes these are backend things that don't make a big difference to users - but this is kind of a cool one!
Let me set the scene.
When you're part of a chat with lots of activity, especially lots of chats all happening at the same time, sometimes it can be hard to know what people are replying to. This feature allows us to specifically reply to a message in a text.
You can click the ... after a message and choose Reply.
When you reply, it copies the message and displays it with your reply.