An upgrade of Shopify plugin allows creation of custom markup in app.schemaapp. this will be beneficial if markup is required beyond the default markup available with the base plugin. 

In order to upgrade or downgrade you need to be logged into your Shopify account.

To Upgrade:

1. Go to "Apps"

2. Click "Upgrade" button. 


To Upgrade/Downgrade:

1. Go to "Apps"

2. Go to "Settings"

3. Click "Upgrade" (or "Downgrade")

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