Issue #2232605 by alexpott, dawehner, martin107, Cottser, sun: Fixed Themes cannot be uninstalled.
Issue #2338571 by znerol: Remove SessionManager::startLazy().
Issue #2325571 followup by omers: Replace _theme() calls by calls to \Drupal::theme()->render().
Issue #2309889 by tim.plunkett, dawehner: Fixed DrupalKernel requires a Drupal\Core\*\Plugin directory for annotated classes to be discovered.
Issue #2063303 by dawehner, damiankloip, Wim Leers: Fixed A Drupal 8 AjaxResponse that must return a 403, returns a 403 and prints 'A fatal error occurred: '
Issue #2312093 by alexpott, yched, andypost, swentel | xjm: Rename FieldInstanceConfig to FieldConfig.
Issue #2263981 by znerol, beejeebus: Introduce a robust and extensible page cache-policy framework.
Issue #2332885 by cs_shadow, Berdir, fago: Rename AllowedValuesInterface to OptionsProviderInterface.
Issue #2337619 by alexpott: Fixed Drupal\views\Plugin\views\query\Sql::buildCondition is checking for a non existing class.
Issue #2318677 by bluegriff | emma.maria: Fixed Password field focus is interfering with the password indicator strength bar.
Issue #2142441 by Garrett Albright: Fixed [Followup needed] CSS aggregator prepends data: URLs with paths.
Issue #2238149 by Berdir, swentel: Apply formatters and widgets in EntityTestFormCotroller.
Issue #2098419 by larowlan | fago: Fixed Missing default access for all comment fields.
Issue #2325801 by jibran, larowlan: Abstract contact module mail delivery out of form into a service.
Issue #2228745 by Wim Leers, sqndr, nod_, undertext: Fixed Color module doesn't look for CSS files declared in a library.
Issue #2211633 by EclipseGc: Provide a composer.json file for Drupal\Component\Plugin.
Issue #2333395 by Jelle_S, attiks: Add sizes to template_preprocess_image.
Issue #1822048 by dawehner, tim.plunkett, damiankloip, EclipseGc, martin107, neclimdul: Introduce a generic fallback plugin mechanism.
Issue #2321809 by undertext, JeroenT | dawehner: Put the access manager onto \Drupal.
Issue #2338479 by rpayanm | dawehner: Convert \Drupal\views\Plugin\Derivative\ViewsMenuLink to use DeriverBase.