Issue #3421016 by quietone, godotislate: Convert MigrateProcessPlugin plugin discovery to attributes

Issue #3431452 by godotislate, smustgrave, alexpott: Rename RenderElement and FormElement plugin abstract classes to RenderElementBase and FormElementBase

Issue #3421439 by godotislate, sorlov, quietone, smustgrave, alexpott, larowlan, longwave, andypost: Convert form and render element plugin discovery to attributes

Issue #3109970 by znerol, andypost, Prashant.c, daffie, Wim Leers, dww, catch: Convert uses of $_SESSION in forms and batch

Issue #3421017 by mohit_aghera, smustgrave: Convert LanguageNegotiation plugin discovery to attributes

Issue #3420986 by kim.pepper, sorlov, larowlan, mstrelan: Convert Condition plugin discovery to attributes

Issue #3385550 by lauriii, Gauravvvv, sboden, Shabbir, longwave: Language negotiation breaks updating Drupal 9 to 10

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

Issue #3364109 by Wim Leers, effulgentsia, lauriii, phenaproxima, borisson_, bircher, alexpott: Configuration schema & required values: add test coverage for `nullable: true` validation support

Issue #3405800 by alexpott, phenaproxima, Wim Leers, bircher, larowlan: Config collections do not trigger configuration events consistently

Issue #3351458 by dburiak, Mingsong, Mahima_Mathur23, sthomen, smustgrave, catch, alexpott: [regression] Language switcher block returns links to node on the frontpage

Issue #3210684 by joachim, mikran, tobiasb: Put each entity type table into a details element on admin/config/regional/content-language

Issue #3252386 by alexpott, longwave, duadua, mondrake, mstrelan, andypost, Spokje, VladimirAus, catch, effulgentsia, Berdir, xjm, bircher, joachim, larowlan: Use PHP attributes instead of doctrine annotations

Issue #3364506 by Wim Leers, effulgentsia, catch, lauriii, borisson_, smustgrave, tim.plunkett, Dave Reid: Add optional validation constraint support to ConfigFormBase

Issue #3209249 by quietone, smustgrave, bharath-kondeti, ankithashetty, KapilV, longwave, Spokje: Fix spelling for 29 migrate translation related words

Issue #3361534 by Wim Leers, borisson_, longwave, catch: KernelTestBase::$strictConfigSchema = TRUE and BrowserTestBase::$strictConfigSchema = TRUE do not actually strictly validate

Issue #2228799 by pmagunia, mohit_aghera, rpayanm, lalitware, AkashKumar07, quietone, bnjmnm: Change page title "Content language" when Content Translation module is enabled

Issue #3336780 by diegors, schlaukopf, xjm, fabiansierra5191: Correctly capitalize "url" in documentation only, part 2

Issue #3134349 by sleitner, yookoala, sharma.amitt16, Akram Khan, penyaskito, sahil.goyal, swatichouhan012, s_leu, larowlan, smustgrave, joachim: \Drupal\language\LanguageNegotiator does not handle PluginNotFoundException and break the site completely

Revert "Issue #3134349 by sleitner, yookoala, sharma.amitt16, Akram Khan, sahil.goyal, swatichouhan012, s_leu, penyaskito, smustgrave, joachim, larowlan: \Drupal\language\LanguageNegotiator does not handle PluginNotFoundException and break the site completely"

This reverts commit b279c994.

Issue #3134349 by sleitner, yookoala, sharma.amitt16, Akram Khan, sahil.goyal, swatichouhan012, s_leu, penyaskito, smustgrave, joachim, larowlan: \Drupal\language\LanguageNegotiator does not handle PluginNotFoundException and break the site completely

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

Issue #3348592 by alexpott, kunal_sahu, joseph.olstad, catch, larowlan, amaria, james.williams, longwave: [regression] Language switcher block throws exception when no route is matched

Issue #3328454 by xjm, Bhanu951, jidrone, smustgrave: Replace most strpos() !== FALSE or === FALSE with str_contains()

Issue #2883450 by mohit_aghera, Patrick Bauer, lauriii, corneboele, aarti zikre, madhu_h, TBI, smustgrave, svdhout: Missing url prefix on language neutral content

Issue #3130751 by stefanos.petrakis, Medha Kumari, larowlan, alexpott, jungle: Fix LanguageNegotiationContentEntity::getLangcode() errors thrown

Issue #2574981 by Manjit.Singh, dimaro, wengerk, darol100, izus, pguillard, vsujeetkumar, Himanshu5050, snehi, paulocs, rakesh.gectcr, jofitz, _utsavsharma, charginghawk, rajeshwari10, sdstyles, quietone, benjifisher, marcusvsouza, LoMo, joelpittet, justAChris, cilefen, YesCT, mradcliffe, spitzialist, annajl, jhodgdon, catch, alexpott, Sabbi0612, kattekrab, Mile23, antojose, leanderl, rodrigoac: Fix grammar ("an URL" should be "a URL") and consistent use of URL (not "url" / "Url") in documentation only

Issue #3126127 by stefanos.petrakis, andypost, xjm, pooja saraah, Kristen Pol: Fix LanguageNegotiationMethodInterface::getLangcode() result docblock

Issue #3324838 by Spokje: Fix PHPStan L2 error "PHPDoc tag @throws with type Foo is not subtype of Throwable"

Issue #3268818 by ravi.shankar, quietone: Fix class comment doc blocks in non tests 'Drupal.Commenting.DocComment.ShortSingleLine'

Issue #3316136 by julien.sibi, flocondetoile: LanguageNegotiationInterface.php : function's name error in docblock

Issue #3181778 by quietone, longwave, aldairsoares, beatrizrodrigues, Aline Teixeira Ramos, KapilV, raman.b, anushrikumari, CChiste, mallezie, Ratan Priya, rakesh.regar, Kevin.Notari, vicheldt, mauryarahul11, yogeshmpawar, bbrala, alexpott, bruno.bicudo: [w/c September 17th] Replace t() with $this->t() in all plugins

Issue #2937515 by Spokje, quietone, idebr, longwave, SherFengChong, anweshasinha, borisson_, mfernea, xjm, bbrala, daffie, Berdir: Fix Drupal.Array.Array.[ArrayClosingIndentation, ArrayIndentation] coding standard

Issue #1987504 by mohit_aghera, quietone, xjm, mandarmbhagwat78, neRok, larowlan, Berdir: Inconsistent character casing for entity type labels