How do I change the small icon shown in the browser tab for my store?

That icon is the favicon.

1. Go to Settings → Web Settings → General Settings.
2. Under Favicon, click Upload image (or Change image) and pick or upload an image from your media gallery.
3. Click Submit.

Use a small square image, for example 64×64 or 512×512 pixels in PNG. Square images look sharpest. The same icon is used when shoppers save your store to their phone's home screen.

If you click Remove (use default), a default Wcart icon is shown instead. Browsers cache favicons, so you may need to refresh or open a new tab to see the change.