How To Turn On the Sender Time Zone Lab Feature?
- Open Gmail and click on the settings link. Then click on the labs tab.
- Once in the labs, scroll down to find the Sender Time Zone feature. Enable it and save the settings.
How it Works?
Every email message contains a header which contains all the information about the sender and the receiver, like IP addresses, time zone information etc. Gmail uses the time zone information from these headers to display these icons