Triaged
-------
https://code.djangoproject.com/ticket/27041 - Note that middleware included with Django is compatible with both MIDDLEWARE and MIDDLEWARE_CLASSES (fixed)
https://code.djangoproject.com/ticket/25931 - ContentTypes population doesn't work with backwards migrations (fixed)
https://code.djangoproject.com/ticket/27048 - Document that refresh_from_db() doesn't clear @cached_properties (fixed)
https://code.djangoproject.com/ticket/27051 - Exception when using only whitespace characters as e-mail subject (wontfix)
https://code.djangoproject.com/ticket/27046 - http.request does not support ipv6-formatted ipv4 addresses (fixed)
https://code.djangoproject.com/ticket/27052 - Malformed url of uploaded files; uploaded_to parameter is ignored (invalid)
Authored
--------
https://github.com/django/django/pull/7030 - Refs #27025 -- Fixed a servers test on Python 3.6.
https://github.com/django/django/pull/7045 - Fixed #26973 -- Fixed views.static.serve() crash with show_indexes enabled.
https://github.com/django/django/pull/7048 - Refs #27025 -- Fixed a couple timezone tests for Python 3.6.
https://github.com/django/django/pull/7057 - Fixed #27045 -- Documented that AUTH_PASSWORD_VALIDATORS aren't applied at the model level.
https://github.com/django/django/pull/7074 - Fixed #19222 - Documented that default managers aren't used for related queries.
Reviewed/committed
------------------
https://github.com/django/django/pull/7031 - Fixed #26764 -- Fixed Session.cycle_key() crash on unaccessed session.
https://github.com/django/django/pull/7020 - Fixed #27002 -- Prevented double query when rendering ModelChoiceField.
https://github.com/django/django/pull/7047 - Fixed #27036 -- Made locmem email backend's send_messages() accept generators.
https://github.com/django/django/pull/6865 - Fixed 26830 -- Prevented the 'with' templatetag from resetting the cycle variable to its initial state.
https://github.com/django/django/pull/6938 - Fixed #13809 -- Made FieldFile.open() respect its mode argument.
https://github.com/django/django/pull/7052 - Fixed #27035 -- Eased changing settings.DEBUG for DiscoverRunner.
https://github.com/django/django/pull/6932 - Fixed #26905 -- Allowed using MultiValueDict-like objects as form data.
https://github.com/django/django/pull/6977 - Fixed #26951 -- Allowed AuthenticationForm to work with a username of 0.
https://github.com/django/django/pull/6986 - Fixed #26960 -- Added PasswordResetConfirmView option to automatically log in after a reset.
https://github.com/django/django/pull/6930 - Fixed #26844 -- Made formset's validate_min validation ignore empty forms.
https://github.com/django/django/pull/6962 - Fixed #26909 -- Allowed UserAttributeSimilarityValidator to validate against model properties.
https://github.com/django/django/pull/7025 - Fixed #27019 -- Made teardown_test_environment() restore the original value of DEBUG.
https://github.com/django/django/pull/7059 - Fixed #26957 -- Corrected authenticate() docs regarding User.is_active.
https://github.com/django/django/pull/6974 - Fixed #26947 -- Added an option to enable the HSTS header preload directive.
https://github.com/django/django/pull/6906 - Fixed #26891 -- Fixed lookup registration for ForeignObject.
https://github.com/django/django/pull/6898 - Fixed #24442 -- Improved SchemaEditor's index name truncation.
https://github.com/django/django/pull/6941 - Fixed #26919 -- Added the action form's media in the changelist view.
https://github.com/django/django/pull/7049 - Fixed #27037 -- Prevented required attribute on ClearableFileInput when initial data exists.
https://github.com/django/django/pull/6982 - Fixed #20888 -- Added support for column order in class-based indexes.
https://github.com/django/django/pull/6902 - Fixed #27007 -- Handled non-UTF-8 bytes objects for text/* attachments.
https://github.com/django/django/pull/7046 - Fixed #27030 -- Added contrib.postgres.indexes.GinIndex.
https://github.com/django/django/pull/7060 - Fixed #27008 -- Added --debug-mode option to DiscoverRunner.
Reviews of core dev work
------------------------
https://github.com/django/django/pull/7015 - Fixed #26500 -- Added SKIP LOCKED support to select_for_update().
https://github.com/django/django/pull/7036 - Fixed #27024 -- Prevented logging error with empty string as geometry widget value.
https://github.com/django/django/pull/7039 - Fixed #27029 -- Fixed EmailValidator to allow non-ASCII characters in local part of the address.