The pages shown in the explorer can now be customised using a new hook called :ref:`construct_explorer_page_queryset <construct_explorer_page_queryset>`.
The ``Document`` model can now be overridden using the new ``WAGTAILDOCS_DOCUMENT_MODEL`` setting. This works in the same way that ``WAGTAILIMAGES_IMAGE_MODEL`` works for ``Image``.
Wagtail no longer depends on the `django-compressor <http://django-compressor.readthedocs.org/>`_ library. While we highly recommend compressing and bundling the CSS and Javascript on your sites, using django-compressor places additional installation and configuration demands on the developer, so this has now been made optional.
* Snippets now support a custom ``edit_handler`` property; this can be used to implement a tabbed interface, for example. See :ref:`customising_the_tabbed_interface` (Mikalai Radchuk)
* The ``Page.path`` field is now explicitly given the "C" collation on PostgreSQL to prevent tree ordering issues when using a database created with the Slovak locale
As Wagtail no longer installs django-compressor automatically as a dependency, you may need to make changes to your site's configuration when upgrading. If your project is actively using django-compressor (that is, your site templates contain ``{% compress %}`` tags), you should ensure that your project's requirements explicitly include django-compressor, rather than indirectly relying on Wagtail to install it. If you are not actively using django-compressor on your site, you should update your settings file to remove the line ``'compressor'`` from ``INSTALLED_APPS``, and remove ``'compressor.finders.CompressorFinder'`` from ``STATICFILES_FINDERS``.
