Later this year Google revamped Gmail interface in February, now the newly rolled out features include dedicated tabs for Meet, Spaces, Chat, and Mail in the left sidebar. Several users find this feature irritating, so there is an option to disable them.
Enable or Disable New Gmail UI
1. Go to the Gmail site and click on the Settings gear icon at the top-right corner
of the screen.
2. Quick settings panel pops up, click on "Try out the new Gmail view", now enable the new Gmail interface.
3. The confirmation prompt appears, click"Reload", the new Gmail view.
4. Now the Gmail UI with tabs for Spaces, Meet, Chat and Mail on left sidebar appears.