A favicon is an icon or image associated with your website that appears in your web browser's address bar or tab, or with the site name in a list of bookmarks.
To add one to your website go to General Settings > General. Add your Favicon under Site Basics.
Click Change Image to upload an image file or use a stock image, similar to an image element or block.
When cropping your image, it will default to a square to preserve the quality of the favicon once it is published.
Once you have cropped your image, an example of how your favicon will look in a browser tab will appear in your settings. Be sure to Publish your website for changes to take effect.
NOTE: If you delete your favicon and re-publish your site, it is possible your favicon will still appear in the address bar. This is resolved by clearing your browser cache. Favicons are not supported in the current version of the Safari browser.