Adding a subject line to a message makes it a lot more scannable for everyone else. To do that, first you need to expand your compose box by clicking format icon. From there, just type the subject line you want in the first line of your expanded compose box.
An error occurred while saving the commentSuresh C R commented
this is already available in skype. when we click on a person in an email, skype automatically adds the chat subject to the IM. so we need the same feature in teams too