Callbar automatically checks every 15 minutes for updates. If a new update exists, it will display a message with an 'Update now' button that you can click to update the Callbar. Please note that due to the way updates are progressively distributed by Google, it may take a few hours for everyone to receive the notification.
Alternatively, you can force an update immediately by following these steps:
- Copy and paste chrome://extensions/ into your browser
- Click the "Developer Mode" checkbox at the top of the page
- Click on "Update extensions now"