Installing plugins has a new interface and themes can now be installed using the back-end.

Default context of manage and pivot forms is now create and update respectively, instead of the old value relation. Use the context option to set it back to the old value (see Backend > Relations docs).

Belongs-to-many model relations now support defining a custom pivot model with the pivotModel option (see Database > Model docs).

The config definitions for behavior RelationController have been refactored. When using pivot mode all columns and fields should now reside in a pivot[] array (see Backend > Relations docs).

Record Finder form widget now supports nested attributes for relations.

List columns now support using array names (eg: relation[attribute]) which acts as an alias for the valueFrom option with searchable and sortable disabled.

Form Tabs now support specifying a default tab using the defaultTab option (see Backend > Forms docs).

Improved the Theme management features: Edit properties, import, export, duplicate and delete.

Form fields can now use a simpler interface for using the Input preset converter (see Backend > Forms docs).

The event cms.page.init no longer passes the URL as the third parameter, $controller->getRouter()->getUrl() should be used instead.

Page::url() no longer takes a third argument for $absolute, generated URLs with this method are always absolute.

Improvements made to the user menu in the back-end: clicking your avatar will display a popover with settings links from the mysettings context.