State/nonce parameter missing from app auth

[dewhaskins]

As of about 16 hours ago I am seeing requests received back from Shopify during the authentication process for our app without the state parameter, which results in failed authentication.

I have tried temporarily ignoring the nonce check to allow authentication to occur but our request back to Shopify gets a 400 Bad Request response. 

Is anyone else having problems with this? 

[EBC]

I can confirm that this also happens to our apps. Sometimes "state" query parameter is simply omitted from the request.