Issue #3222251 by bbrala, longwave: [November 8, 2021] Replace all isset constructs with the null coalescing operator

Issue #2911606 by andypost, jludwig, msankhala, brathbone, imalabya, RajeevChoudhary, benjifisher: Replace usage of the deprecated LOCALE_PLURAL_DELIMITER constant

Issue #2935256 by Jo Fitzgerald, voleger, kim.pepper, ibustos, Yogesh Pawar, catch, jibran: Remove all usages of drupal_get_message and drupal_set_message in modules

Issue #2873696 by nvexler, wengerk, gido, Jo Fitzgerald, xjm: Add @internal to core classes, methods, properties to Form Classes

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

Issue #2560641 by alexpott, lauriii, Xano, borisson_, ianthomas_uk, olli: Remove all usages SafeMarkup::checkPlain() from render arrays

Revert "Issue #2560641 by alexpott, lauriii, Xano, borisson_, ianthomas_uk: Remove all usages SafeMarkup::checkPlain() from render arrays"

This reverts commit 31007609.

Issue #2560641 by alexpott, lauriii, Xano, borisson_, ianthomas_uk: Remove all usages SafeMarkup::checkPlain() from render arrays

Issue #2557519 by alexpott, joelpittet: Remove many usages SafeMarkup::checkPlain() and replace with Html::escape()

Issue #2454829 by maxocub, eiriksm, rvilar, Gábor Hojtsy, penyaskito, tstoeckler, Jose Reyero: Configuration translation UI does not support plural sources/targets

Issue #2420737 by rodrigoaguilera, Pere Orga, Gábor Hojtsy, maxocub, jhodgdon, penyaskito, plach, danigrrl: Differences in dynamic language names are confusing in views, content, etc

Issue #2453761 by Gábor Hojtsy: Views numeric formatter's plural formatting setting incompatible with many languages

Issue #2457887 by prateekMehta, stefan.r, rpayanm, alexpott: Use Utility\SafeMarkup class instead of Utility\String for placeholder(), checkPlain(),format() functions

Issue #2433599 by Wim Leers: Ensure every (non-views) pager automatically associates a matching cache context

Issue #2328293 by keopx, JeroenT, ianthomas_uk, ashutoshsngh, rpayanm, hudo, a_thakur: Remove usage of language_list()

Issue #2309737 by rpayanm, hussainweb, max-kuzomko, herom, millerbennett, ianthomas_uk, quietone, Sutharsan, sumitmadan, toddmbloom: Remove deprecated format_plural usage

Issue #1938916 by joelpittet, akalata, a-fro, duellj, InternetDevels, lauriii: Convert locale theme tables to table #type

Issue #2341341 by YesCT, martin107, vijaycs85, fran seva: Change public 'name' property access on languages to getName() and add back setName().

Issue #2308821 by tim.plunkett: Replace FormErrorInterface with $form_state->setErrorByName() and $form_state->setError().

Issue #2272481 by herom, ParisLiakos, tim.plunkett: Remove usages of watchdog() from forms, plugins and controllers.

Issue #1533250 by YesCT, fran seva, TravisCarden, xjm, sriharsha.uppuluri | NROTC_Webmaster: Many coding standards clean-ups in locale module.

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

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 #2145007 by tim.plunkett, h3rj4n: Convert form_set_error() in FormBase classes to use FormErrorInterface.

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