The export action has been moved from ListController behavior to Import / Export behavior (see Backend > Importing & Exporting docs).

Plugins can now be frozen to prevent them from receiving updates via the plugin management area.

A plugin version can now be flagged as "Important" by prepending !!! to the version history comment.

List columns now support specifying a default option used when the value would otherwise be null.

Implement a custom autoloader for plugins that use composer. Now only one instance of composer is used, all packages are now added to a global pool to prevent double loading and the load order is respected.

The method signature of Model::save() has been fixed to match Eloquent.

Added new security config option cms.enableCsrfProtection.

Protected images and their thumbnails are now supported in the back-end.

Editing CMS templates now support form fields that use AJAX.

When inserting a new link the Rich Editor now shows a drop-down list with available pages.

File Upload form widget can now specify mimeTypes to define MIME types that are accepted by the uploader, either as file extension or fully qualified name.

Introduced the October Storm client-side library.