What does it mean when someone says pop at the end of a message?

When someone says "pop" at the end of a message, it can indicate a few things, often depending on the context. It might be a casual way to express excitement or enthusiasm, akin to saying "cool" or "awesome." In some cases, it could also imply a desire for a quick response, as in "pop back to me when you can." Overall, it's a light-hearted, informal sign-off.