If you’re wondering why the red envelope in your Gmail tab in Chrome turned into a blue-and-yellow cog, the short answer is that it’s a mistake and Google is working on fixing it.
This is the new favicon for the Google Apps Admin Console. It is definitely nothing to worry about. It is currently being displayed for some users in Gmail as well. This is not intended. This issue is currently being worked on and will be resolved as soon as possible.
- Click the Gmail cog drop down and go to Settings
- Go to Labs and search for Unread
- Enable Unread Message Icon