I keep seeing Bing in my optional updates. It gives a little information but I'm still confused. Bing Desktop sets the daily Bing photo as the desktop background and adds a floating search bar. It DOES change the background daily.. Windows 10 Pro - Start10 - part of a local network which is a '3rd party optimizer-free' zone..
2.2.4 HTTP OPTIONS Response. After receiving an HTTP OPTIONS request, a server responds with an HTTP OPTIONS response that specifies the protocol versions it supports.
Support for the $format Query Option. The OData protocol supports both JavaScript Notation (JSON) and Atom feeds, and OData provides the $format system query option to allow a client to request the format of the response feed. This system query option, if supported by the data service, must override the value of the Accept header of the request. WCF Data Services supports returning both JSON and Atom feeds. However, the default implementation does not support the $format query option and uses only the value of the Accept header to determine the format of the response.