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

Issue #2511472 by Wim Leers, Fabianx, dawehner: Refactor all usages of drupal_render()/Renderer::render() that break #2450993

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

Issue #2273925 by larowlan, aneek, lauriii, mikey_p, joelpittet, dimaro, Fabianx, xjm, jaredsmith, effulgentsia, lokapujya, iMiksu, chx, YesCT, googletorp, dawehner, Wim Leers, Cottser: Ensure #markup is XSS escaped in Renderer::doRender()

Issue #2254865 by Wim Leers, lauriii, borisson_, JeroenT, alexpott, Fabianx: toolbar_pre_render() runs on every page and is responsible for ~15ms/17000 function calls

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

Issue #2473105 by ifrik, jhodgdon, lostkangaroo, opratr, LinL: Update hook_help texts that link to modules that can be uninstalled

Issue #2383865 by mgifford, pguillard, rpayanm, alexpott, jhodgdon: Spellchecking Drupal - Javascript

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 #2154475 by tarekdj, neelam.chaudhary, droplet, nod_, lanchez, Poornima3, jamin_melville: Convert position selectors to be compatible with with jQuery native-API selector

Issue #2448605 by martin107, willzyx, tim.plunkett, klausi, dpopdan: Replace usages of drupal_get_destination() with the redirect destination service

Issue #2457781 by prateekMehta, stefan.r, AjitS, hussainweb: Use Utility\Html class instead of Utility\String for decodeEntities() function

Issue #2404603 by mpdonadio, dawehner, larowlan, RavindraSingh: Add proper support for Url objects in FieldPluginBase::renderAsLink(), so we can remove EntityInterface::getSystemPath()

Broke testing UI. Reverted.

This reverts commit dc5ef576.

Issue #2382543 by rpayanm, ianthomas_uk: Remove usage of drupal_html_class() and drupal_clean_css_identifier()

Issue #2384165 by tibbsa: Clean-up Contextual module test members — ensure property definition and use of camelCase naming convention

Issue #2371457 by DuaelFr: Replace inappropriate translatatable string in core/modules/contextual/contextual.module.

Issue #2350949 by Wim Leers: Add hook_page_attachments(_alter)() and deprecate hook_page_build/alter().

Needs more discussion.

This reverts commit b983fad1.

Issue #2347465 by tim.plunkett, dawehner, cilefen: Convert all instances of #type link/links to convert to use routes.

Issue #2350301 by mitrpaka: Replace extend of deprecated DrupalUnitTestBase with KernelTestBase in Contextual.

Issue #2328411 by dawehner, geerlingguy, herom: Convert all permissions to yml files and permission callbacks.

Issue #2221433 by damiankloip, dawehner: Clean up views rendering. Move stuff from template_preprocess_views_view(), into a #pre_render callback.