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 #2224691 by Sweetchuck: JavaScript Drupal.t and Drupal.formatPlural only works for non-english languages.

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 #2203407 by nod_, sun: Replace #attached library array values with provider-namespaced strings.

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 #2198343 by damiankloip, longwave: Convert all usages of cache() and cache_invalidate_tags() procedural functions.

Issue #2182265 by Sweetchuck, nod_: Javascript file translations are several bugs away from working at all.

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 #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 #1998088 by ParisLiakos, alexpott, ebrowet, plopesc, dawehner, Gábor Hojtsy: Convert locale_translate_english variable to CMI.

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

Issue #2002650 by mrsinguyen, chertzog, legolasbo, Erik Erskine, rhm50, sandergo90, grisendo, targoo, janstoeckler, maximpodorov, beowulf1416: Improve maintainability by removing unused local variables.

Issue #1981368 by tim.plunkett, Crell, webchick: Convert all routes to 'module_name().foo_bar()' naming convention.

Issue #2003592 by andypost, mhagedon, webflo: Convert language_admin_add_form() and language_admin_edit_form() to a Controllers.

Issue #1978916 by likin, YesCT, disasm, ayelet_Cr, tim.plunkett, vijaycs85, Letharion: Convert locale_translate_page() to a Controller.

Issue #2035721 by Wim Leers, Gábor Hojtsy: Figure out how to translate Drupal-specific CKEditor plugins.

Issue #2009654 by Cottser, InternetDevels, jesse.d, Carolyn, jenlampton: Replace theme() with drupal_render() in locale module.

This reverts commit 8ce27f22.

Issue #1978928 by piyuesh23, InternetDevels, disasm: Convert locale_translation_manual_status() to a Controller.

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