Framework 22
Adds new subsite settings for Twitter card image sizes.
Framework 21
Adds new subsite settings for Content Security Policy headers.
Framework 20
The image media component used for responsive images can now be set manually in the subsite settings.
Framework 19
Framework 19 adds new features to the Authentication template which make the user registration and password reset journey more seamless.
Framework 18
Framework 18 adds new gallery and highlight box inlines, as well as standardising the image inline. It also implements shared search and logo components that can be used by all of the site themes. The Google Analytics library has been changed to gtag.js
Framework 17
Framework 17 introduces Progressive Web App (PWA) capabilities to sites, makes "page last updated" and "page feedback" functionality available to all themes, and improves the appearance of the Document Section template in search results.
Framework 16
Framework 16 adds session timeout notifications for forms and login sessions.