14 November 2017 Outlook.com and the Outlook iOS app added support for CSS background images and some related properties, as well as certain Flexbox and Grid properties. Also added iOS 11 Mail to the guide, with no noticeable differences from iOS 10. 13 September 2017 A complete rewrite and redesign of the guide, testing 278 different CSS properties and features across 35 email clients. To accommo
