Issue #1754246 by webflo, swentel, penyaskito, andypost, alexpott, YesCT, dagmar: Languages should be configuration entities.

Issue #2031115 by tim.plunkett: Fixed Language::LANGUAGE_DEFAULT should be Language::LANGCODE_DEFAULT.

Issue #1887480 by Sutharsan, webflo: Fixed Automated download of translations when adding languages/enabling modules can not be disabled.

Issue #2010122 by jeroen12345, helga.chb, heddn: Replace theme() with drupal_render() in image module for theme_image_crop_summary().

Issue #2028585 by ParisLiakos, dawehner, tim.plunkett: Replace entity_page_create_access() by an access controller.

Issue #2026769 by fgm: Fixed Simplify DerivativeInterface implementations by refactoring duplicated code to a base class.

Issue #1987856 by vijaycs85, mparker17, sidharthap: Convert system_timezone() to a new style controller.

Issue #2029075 by kfritsche, penyaskito: Fixed Configuration translation step in the installation takes a reeeeaaallly long time when installing in a non-English language.

Issue #1879120 by quicksketch, Wim Leers, larowlan, frega: Use Drupal-specific image and link plugins — use core dialogs rather than CKEditor dialogs, containing alterable Drupal forms.

Issue #1938892 by JohnAlbin, Pancho: Fixed Switch from ISO-3166-1 country data to CLDR unicode data.

Issue #1938892 by JohnAlbin, Pancho: Fixed Switch from ISO-3166-1 country data to CLDR unicode data.

Issue #2022549 by valdo, ParisLiakos, YesCT: Regression: No interface translation in the first installer steps.

Issue #1988508 by katbailey: Stop pretending we support Symfony bundles when we really just have service providers.

Issue #2015789 by fubhy, echoz, rteijeiro, LewisNyman, penyaskito: Remove language_css_alter() (RTL stylesheets) in favor of HTML 'dir' attribute.

Issue #2025991 by plach, David Hernández: Introduce hook_entity_prepare() to generalize hook_node_prepare().

Issue #1810320 by alarcombe: Remove EntityTranslationControllerInterface::getAccess() once have entity access.

Issue #1974376 by kim.pepper, cbiggins, stella, pwieck: Convert aggregator_page_categories() to a Controller.

Issue #2014033 by kgoel, hussainweb: Replace drupal_container() with Drupal::service() in the content_translation() module.

Issue #1898426 by Floydm, Cottser, jenlampton, chrisjlee, kattekrab, jerdavis, derheap, hussainweb: link.module - Convert theme_ functions to Twig.

Issue #2020221 by StephaneQ: Update image module description (in yml) mention that an image field is provided.

Issue #2025325 by naxoc, pplantinga, jessebeach: Fixed Add custom block action results in a fatal error.

Issue #1337554 by LewisNyman, Bojhan, YesCT, Cottser, jenlampton, Xano, David_Rothstein, larowlan, nilnullvoid: Develop and use separate branding for the installer.

Issue #2008990 by heddn, InternetDevels, giammi: Replace theme() with drupal_render() in dblog module.