What is message pinning?
When you pin a message, it sticks the message to the top of your inbox. This is useful when an older message is important, and you want it to appear alongside with your recent messages.
This can help with reminding you to reply. In addition, you can use Pin to keep things “top of mind” like important Tasks or Notes that you constantly use. For example, keeping a long task list of miscellaneous tasks that is constantly updated. This is perfect for tasks without a deadline that would need you attention someday.