Issue #3187004 by recrit, a.dmitriiev, mohit_aghera, ranjith_kumar_k_u, larowlan, Matroskeen, smustgrave, Kristen Pol, neclimdul: DrupalDateTime serialization issue

Issue #3009377 by kim.pepper, andypost, Berdir, alexpott, Wim Leers, mpdonadio, acbramley, larowlan, catch, xjm: Replace drupal_get_user_timezone with a date_default_timezone_get() and an event listener

Issue #2924781 by osman, yogeshmpawar, zaporylie, mfernea: Missing @var annotation for scalars that do not provide default values

Issue #2933424 by David_Rothstein, harsha012, jhodgdon, vaplas: English-specific links to php.net shouldn't be used in non-translatable strings

Issue #2901726 by mfernea, gmario, finn.lewis, robertoperuzzo, rachel_norfolk: Fix 'Squiz.Functions.MultiLineFunctionDeclaration' coding standard

Issue #2889814 by mpdonadio: DateTimePlus doesn't apply the correct time zone when converting a string with an offset

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 #2716685 by Mile23: Part 2: Fix several errors in the 'Drupal.Commenting.DocComment' coding standard

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

Issue #2572643 by alexpott, attiks, Jelle_S, jhodgdon: Fix Drupal.Commenting.FileComment coding standard

Issue #2596043 by mpdonadio, pjonckiere: DrupalDateTime constructor claims to support \DateTime object - it should not

Issue #2568613 by alexpott, lauriii, pwolanin: Remove HTML support from date formats and replace remaining !placeholder where format_date() and 'date.formatter' => format() are used

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

Issue #2497447 by mpdonadio, stefan.r, jhodgdon: DrupalDateTime::format() and DateTimePlus::format() ignore the timezone setting

Issue #2429443 by vijaycs85, rteijeiro, penyaskito, gloob, xjm, nod_, geertvd, pjonckiere, alexpott, Wim Leers, Gábor Hojtsy, Fabianx, tim.plunkett: Date format form is unusable

Issue #2457251 by vijaycs85: Remove unnecessary call to drupal_get_user_timezone() in Drupal/Core/Datetime/DrupalDateTime::prepareTimezone() method

Issue #2116327 by martin107: Creating  DrupalDateTime object, with a 'date'  array as input will always fail with exception

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

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

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

Issue #2100329 by cosmicdreams: Use \Drupal instead of Drupal to make IDEs and static code analyse tools happy.

Issue #2000384 by yuradoc, Damien Tournoud, alexpott: Fixed php-intl module causes problems with Date and Time fields when editing Basic Page.

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

Issue #1620010 by dawehner, ParisLiakos, plach, jibran: Move LANGUAGE constants to the Language class.

Issue #1944636 by alexpott, YesCT: Fixed PECL Intl extension usage in DateTimePlus class broken and untested.

Issue #1571632 by cosmicdreams, marcingy, justafish, chx, KarenS, aspilicious, disasm, swentel, dawehner, rvilar: Convert regional settings to configuration system.