Issue #2090983 by plach, Berdir, yched: ContentEntityInterface::getTranslation() should throw an exception when an invalid language is specified

Issue #2493475 by ifrik, walangitan, XaviP, jhodgdon, batigolix: Fix online docs references in Help to conform to our standards

Issue #2560783 by stefan.r, joelpittet, lauriii, Cottser, Sutharsan, kgoel, justAChris, Gábor Hojtsy, dawehner, jhodgdon, effulgentsia, xjm, andypost, googletorp: Replace !placeholder with :placeholder for URLs in hook_help() implementations

Issue #2529034 by penyaskito, vijaycs85, yched: Replace direct access to FieldConfigBase::default_value with methods

Issue #2349819 by amateescu, swentel, Leksat, larowlan, dawehner, Gábor Hojtsy, mpdonadio, benjy, jmuzz, yched, jibran, marthinal, dmsmidt: String field type doesn't consider empty string as empty value

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

Issue #2481453 by dawehner, pwolanin, rteijeiro, neclimdul, znerol: Implement query parameter based content negotiation as alternative to extensions

Issue #2383871 by mgifford, rpayanm, a_thakur, maximpodorov, AohRveTPV, jhodgdon: Spellchecking Drupal - PHP

Issue #2491155 by mikeburrelljr, Mac_Weber, opdavies: Update drupal.org and kernel.org URLs in core modules (Follow-up to 2489912)

Issue #2472323 by dawehner, neclimdul, Crell, kim.pepper, nod_, Wim Leers, larowlan, jibran, pwolanin, catch: Move modal / dialog to query parameters

Issue #2090115 by alexpott, xjm: Don't install a module when its default configuration has unmet dependencies

Issue #2357199 by andypost, naiduharish: Consider CommentManagerInterface::addDefaultField() as deprecated and remove in favour of CommentTestTrait

Issue #2164601 by yched, jibran, amateescu, pfrenssen: Stop auto-creating FieldItems on mere reading of $entity->field[N]

Issue #2358079 by pwolanin, Berdir: Require a specific placeholder format in db_query() in order to trigger argument expansion, and require explicit 'IN' parameter for conditions

Issue #2405091 by marthinal, Berdir, RavindraSingh: Cannot create user entities  - {"error":"Access denied on creating field pass"}

Issue #2364157 by mpdonadio, dawehner, martin107, Berdir, pcambra, naveenvalecha, tim.plunkett: Replace most existing _url calls with Url objects

Issue #2143729 by tstoeckler, plach, jsbalsera, Berdir, mauzeh, damiankloip, andypost: Entity definitions miss a language entity key

Issue #2347999 by Mile23, daffie, cs_shadow, cosmicdreams: DrupalUnitTestBase is deprecated, replace with KernelTestBase

Issue #2365319 by damiankloip, larowlan: Entity normalization should check field access to avoid leaking data

Issue #1426804 by alexpott, swentel: Fixed Allow field storages to be persisted when they have no fields.

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

Issue #2304987 by Berdir, Wim Leers: Fixed Don't invalidate cache tags of referenced entities, use entity list cache tags correctly, add test coverage for entity list cache tags.

Issue #2343661 by larowlan, tim.plunkett | xjm: Rename l() to _l() and url() to _url(), and document replacements.

Issue #2002138 by yched, Jose Reyero, xjm, andypost, fago, msonnabaum, Berdir, dixon_: Use adapters for supporting typed data.

Issue #2312093 by alexpott, yched, andypost, swentel | xjm: Rename FieldInstanceConfig to FieldConfig.

Issue #2336177 by alexpott, YesCT: Fixed ConfigurableLanguage cannot be created/removed directly, integrate language_save() and language_delete().

This reverts commit 3ac426f9.