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

Issue #1898422 by joelpittet, lokapujya, Salah Messaoud, stevector, Les Lim, pplantinga, jenlampton, drupalninja99, tlattimore, johannez | c4rl: Language.module - Convert theme_ functions to Twig.

Issue #2103039 by fran seva, rodrigoaguilera, Gábor Hojtsy, ifrik, batigolix, bendev: Update hook_help for language module

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

Issue #1987726 by vijaycs85, disasm, YesCT, pdrake, tstoeckler, dawehner, Xano, likin, stella, andypost, prateek479, Gábor Hojtsy, kgoel: Convert language content page related callback to new style controller.

Issue #2183113 by jhodgdon, effulgentsia, tim.plunkett, herom, larowlan: Update hook_help signature to use route_name instead of path.

Issue #2240463 by robertdbailey, balagan, holly.ross.drupal: Fix text: languages are not "enabled/disabled" anymore, they are added/removed.

Issue #1870746 by balagan, robertdbailey, lydie, KCarlile, pixelite, fenda | YesCT: Make it obvious what reordering language list does (order in language select) and does not do (fallback detection selection).

Issue #2166915 by ianthomas_uk, sun | plach: Remove uses of deprecated language functions in tests and procedural code.

Issue #2226903 by pwolanin, dawehner, tvn, martin107, jessebeach: Step 1: Move static menu links to yml files.

Issue #2223249 by alexpott: Remove hook_language_insert/update/delete/presave in favour of entity hooks.

Issue #2178725 by pwolanin, crowdcg, effulgentsia, Sutharsan: Make all core menu link machine names and the corresponding route names match.

Issue #2070369 by herom, bdgreen, Mac_Weber, InternetDevels, sidharthap, JeroenT: Remove all calls to deprecated function language().

Issue #1996238 by sun, nod_, damiankloip, Wim Leers, longwave, alexpott, Xano, mdrummond, Mark Carver, Jeff Burnz, highrockmedia, joelpittet, et al: Replace hook_library_info() by *.libraries.yml file.

Issue #2187735 by ianthomas_uk, Sutharsan, andypost: Add removal information to docblock of all @deprecated functions.

Issue #2165155 by Berdir, tim.plunkett: Change $entity_type to $entity_type_id and $entity_info to $entity_type/$entity_types.

Issue #2047633 by pwolanin, dawehner, kim.pepper, Xano, amateescu, tim.plunkett: Move definition of menu links to hook_menu_link_defaults(), decouple key name from path, and make 'parent' explicit.

Revert "Issue #2047633 by dawehner, pwolanin, Xano, amateescu, tim.plunkett: Move definition of menu links to hook_menu_link_defaults(), decouple key name from path, and make 'parent' explicit."

This reverts commit 531fd593.

Issue #2047633 by dawehner, pwolanin, Xano, amateescu, tim.plunkett: Move definition of menu links to hook_menu_link_defaults(), decouple key name from path, and make 'parent' explicit.

Issue #1862202 by plach, Berdir, katbailey, ParisLiakos, alexpott, chx, sun, larowlan, Gábor Hojtsy, cosmicdreams, vijaycs85, YesCT, penyaskito, andypost, Albert Volkman, joelpitett: Objectify the language system.

Issue #2086485 by brianV, jibran, pwolanin, disasm: Convert language_negotiation_configure_form() to the new form interface.

Issue #2005716 by tim.plunkett, msonnabaum, dawehner, alexpott, effulgentsia: Promote EntityType to a domain object.

Issue #2062001 by InternetDevels, DeimoS: Replace user_access() calls with ->hasPermission() in language module.

Issue #2003812 by jsbalsera, Xano, mducharme, NonProfit, shixish | dagmita: Reorder element under configuration => Regional and language.

Issue #2102125 by dawehner, tim.plunkett, neclimdul, pwolanin, YesCT, damiankloip, Tim Bozeman: Big Local Task Conversion.

Issue #2061929 by likin, m1r1k, robmc, InternetDevels: Remove calls to deprecated global  from language.module.

Issue #2004878 by kalabro, DmitryDrozdik, YesCT: Config page title 'Content language settings' misleading after translation is enabled.

Issue #1653026 by damiankloip, alexpott, sun, tim.plunkett, dawehner, mtift: Fixed All configuration values are stored as strings.

Issue #1936216 by stkrzysiak, kfritsche, Schnitzel, webflo, grisendo: Fixed Configuration language selectors should have English even if English is not on the site.

Issue #2049207 by dlu, blakehall, janstoeckler, ramlev, Moderate | Cottser: Replace .tpl.php with .html.twig in documentation.

Issue #1199946 by alexpott, fubhy, bojanz, steinmb, chx, catch: Fixed Disabled modules are broken beyond repair so the 'disable' functionality needs to be removed.