Shopify recently launched advanced authentication mechanism for merchants which our app recently started using. So under some circumstance, you might see failures when you try to load an app.
Failure could be in a form of white screen or seeing connection refused error.
When this happens, it means your browser cookies are conflicting and those needs to be cleared. Don't panic as your FAQs are still intact with us and this is just admin facing issue which can be resolved.
Simple fix is to clear your browser cookies. Please refer to following articles which would help you clearing cookies depending on which browser you are using.
Choose your browser: Google Chrome | Firefox | Safari
If you still persist an issue, please contact us with screenshots and we are more than happy to take a further look.