Issue #2507237 by dimitriskr, twistor, longwave, smustgrave: Replace ReflectionClass::implementsInterface() with is_subclass_of()

Issue #3348686 by james.williams, FeyP, kunal_sahu, larowlan, alexpott: [regression] Inaccessible language switcher links are removed before alternatives can be provided

Issue #2940121 by apaderno, andypost, idebr, Kingdutch, kala4ek, mfb, alexpott, Berdir: ConfigurableLanguageManager::getLanguageSwitchLinks() doesn't respect what LanguageManagerInterface::getLanguageSwitchLinks() says to return

Issue #2189267 by Manuel Garcia, snufkin, alexpott, nuez, maxocub, mirsoft, SiliconMind, blazey, mErilainen, wannesderoy, borisson_, Gábor Hojtsy, stella, spoit, swentel, lauriii, Rob230, Xano, danquah: When content language detection is different from interface language detection, the detected language is not applied to the rendered content

Issue #2806601 by Berdir, amateescu: ConfigurableLanguage is missing config_export property and language.module does untrusted config saves during install

Issue #2776975 by joelpittet, dawehner, tim.plunkett, xjm, pfrenssen: March 3, 2017: Convert core to array syntax coding standards for Drupal 8.3.x RC phase

Issue #2585821 by blazey, marvin_B8, sdstyles, benelori, GoZ, DuaelFr: ConfigurableLanguageManager language_switch_links alter use undefined path variable

Issue #2572777 by andypost, alexpott, attiks, andriyun: Fix 'Squiz.Strings.ConcatenationSpacing' coding standard

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2576533 by alexpott, stefan.r, Wim Leers, dawehner, xjm, effulgentsia, catch: Rename SafeStringInterface to MarkupInterface and move related classes

Issue #2571375 by alexpott, webflo, stefan.r, Xano, mr.baileys: Remove TranslationManager dependency from LanguageManager

Issue #2497275 by borisson_, alexpott, dawehner, Gábor Hojtsy: ~50 calls to t() for two strings in LanguageManager() on every request

Revert "Issue #2497275 by borisson_, alexpott: ~50 calls to t() for two strings in LanguageManager() on every request"

This reverts commit fe4cd2cf.

Issue #2497275 by borisson_, alexpott: ~50 calls to t() for two strings in LanguageManager() on every request

Issue #2493665 by Fabianx, dawehner, msonnabaum, catch: Add centralized container invalidation method

Issue #2392319 by alexpott, effulgentsia: Config objects (but not config entities) should by default be immutable

Issue #1879930 by fran seva, Gábor Hojtsy, martin107, markie, Schnitzel, alexpott, Sutharsan, mon_franco, YesCT, spearhead93, herom, Désiré: Fixed Language selectors are not showing localized to the page language.

Issue #2226533 by martin107, filijonka, YesCT, Xano, jmolivas, Chris Dart, alexpott, tstoeckler, visabhishek | csg: Changes to the Language class due to the LanguageInterface (followup).

Issue #2340667 by YesCT, Pedro Lozano, alexpott, martin107: Protect Drupal\Core\Language\Language::id, and use getId().

Issue #2347465 by tim.plunkett, dawehner, cilefen: Convert all instances of #type link/links to convert to use routes.

Issue #2337847 by alexpott, YesCT, martin107: The negotiated method_id does not need to be sorted on the Language or ConfigurableLanguage object.

Issue #2338055 by martin107: A couple of quirks in the documentation for \Drupal\language\ConfigurableLanguageManager.

Issue #2337849 by martin107 | YesCT: Dont need alias in use for use Drupal\Core\Language\LanguageInterface as BaseLanguageInterface; in LanguageNegotiationMethodInterface.

Issue #2107427 by penyaskito, dclavain, Gábor Hojtsy, mashermike, Aron Novak, YesCT, szato, Wim Leers, mikispeed, vijaycs85: Fixed Regression: Language names should display in their native names in the language switcher block.

Issue #2240459 by Gábor Hojtsy, penyaskito | LoMo: Fixed Applying default language fallback rules to interface translation has impressively bad results.

Issue #2284103 by alexpott, fabpot, damiankloip, Xano, Xen, Berdir: Fixed Remove the request from the container.

Issue #2246665 by jaredsmith, martin107, YesCT, filijonka, tstoeckler: Typehint with Drupal\Core\Language\LanguageInterface instead Drupal\Core\Language\Language.

Issue #2080427 by connork, blainelang, harijari, areke, chertzog: Remove Unused local variables from language module.

Issue #2224887 by alexpott, Berdir, Gábor Hojtsy, Jalandhar: Language configuration overrides should have their own storage.

Issue #2254495 by sun, ParisLiakos, alexpott: Followup to Move language_admin_predefined_list to ConfigurableLanguageManager.

Issue #2254495 by ParisLiakos, alexpott: Move language_admin_predefined_list to ConfigurableLanguageManager.

Issue #2239407 by holly.ross.drupal, YesCT, tstoeckler, alimac: Language manager interface should not specify implementation details for getLanguages on the interface.