Issue #2476407 by borisson_, hussainweb, znerol, Fabianx, Wim Leers, dawehner, Crell, Berdir: Use CacheableResponseInterface to determine which responses should be cached

Issue #2520540 by alexpott: Enforced configuration dependencies shouldn't have to be repeated in the calculated dependencies

Issue #2454649 by Aki Tendo, dawehner: Cache Optimization and hardening -- [PP-1] Use assert() instead of exceptions in Cache::merge(Tags|Contexts)

Issue #2497667 by almaudoh, Wim Leers, Cottser, Fabianx, jaxxed: Add libraries-extend to themes' *.info.yml

Issue #2410497 by alvar0hurtad0, sdstyles, hussainweb, webchick, jhodgdon, mpdonadio: Update remaining url() and _l() calls in comments/documentation

Issue #2576525 by joshi.rohit100, DuaelFr, MattA: Missing package property in *.info.yml files for some testing support modules

Issue #2451411 by almaudoh, Shamsher_Alam, lauriii, borisson_, cilefen, davidhernandez, Cottser, Wim Leers, joelpittet: Add libraries-override to themes' *.info.yml

Issue #2281533 by claudiu.cristea, amateescu, tim.plunkett, yched, jibran, catch: Entity Reference default selection plugin ignores matches if an entity type has no label key

Issue #2575615 by alexpott, pwolanin, stefan.r, catch, dawehner, effulgentsia, xjm, David_Rothstein, iMiksu, lauriii, joelpittet: Introduce HtmlEscapedText and remove SafeMarkup::setMultiple() and SafeMarkup::getAll() and remove the static safeStrings list

Issue #2579021 by Wim Leers, Berdir, sasanikolic, Fabianx: Prevent comment forms from marking rendered nodes as uncacheable

Issue #2576533 by alexpott, stefan.r, Wim Leers, dawehner, xjm, effulgentsia, catch: Rename SafeStringInterface to MarkupInterface and move related classes

Issue #2172843 by fgm, marthinal, pfrenssen, amateescu, andypost, Wim Leers, stefan.r, pwieck, deepak_123: Remove ability to update entity bundle machine names

Issue #2569529 by mdrummond, DuaelFr: system_update_8005 does not create secondary tasks block in Seven

Issue #2547159 by mdrummond, mortendk, davidhernandez, lauriii, joelpittet, Wim Leers, Cottser: menu class generating should be in the template not in a function

Issue #2563801 by rashid_786, sdstyles, keopx, joshi.rohit100, Mile23, lachezar.valchev, NikhilValand: Remove usage of menu_test_theme_page_callback()

Issue #2476947 by mdrummond, Wim Leers, davidhernandez, lauriii, joelpittet, andypost, Cottser, JeroenT, Manuel Garcia, rpayanm: Convert "title" page element into a block

Issue #2558189 by JeroenT, pwolanin, Cyberschorsch, SteffenR, Mile23: Remove usage of deprecated UrlGeneratorInterface::generateFromPath() in system module

Issue #2571695 by dawehner, plach, stefan.r, jaredsmith, lauriii, YesCT, xjm, catch, alexpott, joelpittet, Ryan Weal, Sutharsan, subhojit777, justAChris, nlisgo, effulgentsia, rpayanm, larowlan, chx, geertvd: Remove !placeholder and unsafe string return from SafeMarkup::format()

Issue #2573667 by k4v, YesCT, plach, dawehner, othermachines: Entity uninstallation does not clean up field schema data in state properly

Issue #2508884 by EclipseGc, tim.plunkett, dsnopek, japerry, sravya_12, swathin, Wim Leers, Fabianx, dawehner, yched: Make contexts immutable

Issue #2574717 by dawehner, hussainweb, lauriii, pwolanin, davidhernandez, xjm, stefan.r, webchick, Wim Leers: Remove PHPTemplate, and add test coverage for multiple theme engine support

Issue #2569083 by dsnopek, tim.plunkett, Wim Leers: Allow passing cacheable metadata to display variants (to enable Panels Everywhere)

Issue #2550941 by dsnopek, tim.plunkett, lslinnet: Allow passing contexts to display variants (to enable Panels Everywhere to use static context and relationships)

Issue #2569069 by stefan.r, mr.baileys, alexpott, lauriii: Replace TranslationWrapper with TranslatableString and deprecate TranslationWrapper

Issue #2568977 by alexpott, dawehner, pwolanin, Wim Leers: Replace SafeMarkup::format() in the link generator - it's a bad example to everyone

Issue #2553661 by claudiu.cristea, geertvd, dawehner, Xano, neclimdul: KernelTestBase fails to set up FileCache

Issue #2557113 by stefan.r, alexpott, dawehner, joelpittet, cilefen, lauriii, plach, catch, chx, xjm: Make t() return a TranslationWrapper object to remove reliance on a static, unpredictable safe list

Issue #2477223 by Mile23, Wim Leers, j2r, ianthomas_uk, jaimeguzman, pjbaert: Refactor _drupal_add_html_head, drupal_get_html_head, _drupal_add_html_head_link into the attachments processor, remove from common.inc

Issue #2545972 by alexpott, joelpittet, ericjenkins, stefan.r, Wim Leers, Cottser: Remove all code usages SafeMarkup::checkPlain() and rely more on Twig autoescaping

Issue #2569293 by lauriii, alexpott, dawehner: Replace remaining !placeholder for Non-URL HTML outputs only in code Table.php

Issue #2560863 by alexpott, stefan.r, lauriii: #options for radios and checkboxes uses SafeMarkup::checkPlain() to escape - use Html::escape() instead

Issue #2511516 by lauriii, Xano, Wim Leers, dawehner: Make local tasks and actions hooks provide cacheability metadata, to make the blocks showing them cacheable