How can I enable the upload app in the theme editor?
With the new Shopify Online store 2.0, apps can now be enabled directly in the theme editor.
In the Shopify Admin, navigate to the Online Store menu. Select the theme you want to enable the app in and click on "Customize":
In the editor, click on "App embeds" icon on the left navigation bar:
There you can find the "Upload-Lift App", toggle the switch to enable it:
Make sure to save the theme in the top right corner.
App showing twice
If the app is showing up twice on your store, please visit the following help documentation: App showing twice