Issue #2408371 by dawehner, Fabianx, alexpott, bforchhammer: Proxies of module interfaces don't work

Issue #2509300 by dawehner, catch, larowlan: Path alias UI allows node/1 and /node/1 as system path then fatals

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

Issue #2505197 by Arskiainen, jaimeguzman, tstoeckler: Add a @see + docs about language_element_info_alter() to LanguageSelect

Issue #2483781 by borisson_, rbayliss, cilefen, mitalimehta, joshi.rohit100: Move cache contexts classes from \Drupal\Core\Cache to \Drupal\Core\Cache\Context

Issue #2485409 by rudraram, Manjit.Singh, LewisNyman: Clean up content translation CSS inline with our CSS standards

Issue #2195573 by Xano, eiriksm, heddn, ParisLiakos, Les Lim, Pere Orga, dinarcon, xjm, alexpott: Add a dedicated @LanguageNegotiation annotation class

Issue #1994292 by David_Rothstein, Gábor Hojtsy: LanguageInterface::TYPE_URL (D8) and LANGUAGE_TYPE_URL (D7) have no name or description

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 #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 #2470307 by Mark_L6n, eiriksm, Gábor Hojtsy: Modifying path prefix for URL language detection causes error message for default language

Issue #2335661 by Wim Leers, pwolanin, dawehner, Fabianx, larowlan, catch, Berdir: Outbound path & route processors must specify cacheability metadata

Issue #2428103 by dawehner, amateescu, Berdir, AjitS: String formatter should link to its translation

Issue #2432791 by alexpott, vijaycs85, tim.plunkett, joshtaylor, Fabianx, Berdir, yched, bojanz: Skip Config::save schema validation of config data for trusted data.

Issue #2368987 by Wim Leers, Berdir, Schnitzel, epari.siva, bircher, vijaycs85, likin: Move internal page caching to a module to avoid relying on config get on runtime

Issue #2375689 by Arla, Wim Leers, dawehner, tim.plunkett, Berdir: BlockBase::blockAccess() should return AccessResult instead of a bool

Issue #2031641 by aburrows, lauriii, nlisgo, Pol, redsquid, tuutti, LewisNyman, akalata, agviu, kallehauge, _nolocation, rpayanm, saki007ster, mdrummond, RavindraSingh, brahmjeet789: Change active class to is-active

Issue #2226621 by JeroenT, ianthomas_uk, lokapujya, pjonckiere, marcingy, LinL, Xano, rpayanm, piyuesh23: Remove usage of element_info(), element_child() and element_children(). Deprecate element_info_property()

Issue #2460027 by epari.siva, vijaycs85: Update the documentation of  Drupal\language\LanguageServiceProvider::getDefaultLanguageValues()

Issue #2459971 by Gábor Hojtsy: The langcode key on configuration files is not explicit in configuration schema

Issue #2457271 by rteijeiro, Palashvijay4O, Cottser: More cleanup of the 'themeable' documentation group

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

Issue #2212069 by Gábor Hojtsy, pjonckiere, rteijeiro, cilefen: Non-English Drupal sites get default configuration in English, edited in English, originals not actually used if translated

Revert "Revert "Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code""

This reverts commit 079a52b4.

Revert "Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code"

This reverts commit 364a6e9c.

Issue #2457653 by Gábor Hojtsy: System.site langcode is both used as a file language code and a site language code

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