Issue #1939092 by mgifford, dbazuin, jenlampton, azinoman, pwieck, Cottser, joelpittet, larowlan: Convert theme_mark() to Twig.

Issue #1898070 by benjifisher, jjcarrion, LinL, idflood, joelpittet, oshelach, tlattimore, Les Lim, sergey.semashko, jesse.d, bdgreen, jenlampton, Cottser, duellj, artofeclipse, vlad.dancer, steveoliver, EVIIILJ, c4rl, elv, OpenChimp: File.module - Convert theme_ functions to Twig.

Issue #2151821 by joelpittet, JacobSanford, jjcarrion, rteijeiro, c4rl, IshaDakota, pplantinga, gnuget, longwave, jeanfei, sbudker1: Convert theme_system_config_form() to Twig

Issue #1898420 by mondrake, joelpittet, InternetDevels, claudiu.cristea, c4rl, DamienMcKenna, Albert Volkman, shanethehat, thedavidmeister: Image.module - Convert theme_ functions to Twig.

Issue #2250325 by jhodgdon, azinck, splatio: Fixed Route book.render (path /book) does not seem to work.

Issue #2052473 by ricky.middaugh, lokapujya, Jalandhar, mgifford, jessebeach, BarisW, falcon03: Add aria-label or aria-describedby attributes to all <nav> elements.

Issue #2080343 by connork, izus, rahul.shinde, lokapujya | mrsinguyen: Remove Unused local variables from system module.

Issue #2089331 by grom358 | thedavidmeister: [meta] Replace calls to check_plain() with Drupal\Component\Utility\String::checkPlain().

Issue #2264753 by cfox612, Cottser, a-fro, joelpittet: Convert theme_update_last_check to update-last-check.html.twig.

Issue #2152215 by joelpittet, mr.baileys, benjifisher, martin107, rteijeiro, hussainweb, shanethehat, jenlampton, kpa, AnythonyR, EVIIILJ, kgoel, Cottser, dsdeiz, hanpersand, bayousoft: Convert theme_form_element_label() to Twig

Issue #2282477 by tim.plunkett: Fixed ViewListBuilder::getDisplaysList() does not handle empty admin strings.

Issue #2229163 by Michael Hodge Jr, rixter, thechanceg, bburg | Berdir: Remove node_type->has_title.

Issue #2283929 by tim.plunkett: Clean up condition plugins to have schema support and to allow them to be optional.

Issue #2283969 by tim.plunkett: Add a protected BlockBase::blockAccess() to contain plugin-specific logic.

Revert "Issue #2125621 by anandps, mgifford, davidhernandez, jessebeach, mparker17: Fixed drupala11y.org finds two new color contrast issues."

Needs more discussion/review, given strong visual impact.

This reverts commit cdf25d79.

Issue #2276387 by Gábor Hojtsy, vijaycs85: Fixed Translate routes should properly inherit admin path use from edit route.

Issue #2248405 by davidhernandez, mgifford: Fixed Set Proper Contrast on the Color module's default colour scheme.

Issue #2239425 by cs_shadow, Mixologic, JacobSanford | penyaskito: Invalid TranslatorInterface type hinting in LanguageRequestSubscriber.

Issue #2152219 by joelpittet, mdrummond, rodrigoaguilera, sqndr, rteijeiro, InternetDevels, steveoliver, hussainweb, shanethehat, jenlampton, kpa, AnythonyR, EVIIILJ, kgoel, Cottser, dsdeiz, hanpersand: Convert theme_input() to Twig

Issue #2193691 by holly.ross.drupal, Bojhan, BLadwin | mgifford: New methods, standards for describing Seven themes admin page.

Issue #2255659 by dawehner, xjm, jrbeeman, damiankloip: Added Provide a GET query parameter default argument plugin.

Issue #2125621 by anandps, mgifford, davidhernandez, jessebeach, mparker17: Fixed drupala11y.org finds two new color contrast issues.

Issue #2152205 by joelpittet, mark.labrecque, Manuel Garcia, pakmanlh, steveoliver, hussainweb, shanethehat, jenlampton, kpa, AnythonyR, EVIIILJ, kgoel, Cottser, dsdeiz, hanpersand: Convert theme_date() to #theme input__date

Issue #2252743 by amitgoyal, er.pushpinderrana, jonreid, lexfunk: Rename 'clone' to 'duplicate' for displays in Views UI.

Issue #2266751 by cfox612, Pancho: Fixed Update and improve links styling in preview.css to mirror current values.

Issue #1423244 by tstoeckler, floretan, Wim Leers, lokapujya, xjm, webflo: #allowed_formats property for #type 'text_format' to filter available formats.

Issue #2211723 followup by yched, Berdir: FieldInstance::__construct() loads all field_config entities.

Issue #2277981 by tim.plunkett, EclipseGc, fago: Provide a service for handling context-aware plugins.

Issue #2246665 by jaredsmith, martin107, YesCT, filijonka, tstoeckler: Typehint with Drupal\Core\Language\LanguageInterface instead Drupal\Core\Language\Language.

Issue #2267053 by sidharthap, Daniel Norton, iMiksu, emclaughlin | joachim: Fixed breadcrumb is wrong on single log event pages.