Don't work inside Shopify theme editor

[alvinkonda]

Normally it should work inside Shopify Theme editor as well. On site it works fine.

This is the error we get
Uncaught InvalidAccessError: Failed to set the 'responseType' property on 'XMLHttpRequest': The response type cannot be changed for synchronous requests made from a document.

[yannou788]

@alvinkonda Hello try with my PR #66