Shopware 6: Test extension before code review

I'm developing an app for Shopware 6 app marketplace. I've already created it and tested it in locally running Shopware 6 instance where it has been successfully registered and confirmed with our server.

Now I want to publish the app. For this I had to replace some endpoint to lead to our production servers and replace the secret "App key" from the Shopware Extensions Partner area, created zip file and uploaded it as a release of the extension.

Now I've got an option to submit the app for a review, but before that I would like to thoroughly test the uploaded version.

I see that there is an option to add "Demo shops", but there is no documentation for that and I don't know how to setup one. Maybe local instance exposed to internet through ngrok?

Could someone please explain to me how to test the extension on some live Shopware before submitting it for a code review?

(It's worth noting that our extension consists of just a manifest.xml file and icon.png and is used just as an API connector, it has no other code.)

For development purposes you can make your app private by
providing a hard-coded secret value. You'll just have to remove it before submitting it to the store.

> For local development, you can specify a <secret> in the manifest file that is used for signing the registration request. However, if an app uses a hard-coded secret in the manifest, it can't be uploaded to the store.

<?xml version="1.0" encoding="UTF-8"?>
<manifest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="https://raw.githubusercontent.com/shopware/platform/master/src/Core/Framework/App/Manifest/Schema/manifest-2.0.xsd">
    <setup>
        <registrationUrl>http://localhost/register</registrationUrl>
        <secret>verysecret</secret>
    </setup>
</manifest>