Here is how you can add banners for your shopfront:
Step 1: Click on 'More' on bottom of the main page
Step 2: Click on Shopfront
Step 3: Click on Layouts at the bottom of the screen
Step 4: Enable Show Home Screen on top
Step 5: Click on add new layout
Step 6: Click on Banner
Step 7: Click on Image area and add image
Step 8: Click on save and click on apply changes
This is how it would look like once when you complete uploading a banner
Note: The picture above is just an example, you will get a view of whatever picture you have added
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