Issue #2927723 by longwave, artreaktor, chiranjeeb2410, ankitjain28may, cilefen, dawehner: The URL "/ " with trailing space is not getting recognized as <front>

Issue #2572613 by Malevi4, idebr, pfrenssen, Mile23, RajeevK: Fix 'Drupal.Array.Array.CommaLastItem' coding standard

Issue #2901730 by mfernea, ankitjain28may, idebr: Fix 'Squiz.WhiteSpace.FunctionSpacing' coding standard

Issue #2923496 by mark_fullmer, dpfitzsi, krina.addweb: [Link module] Validation for title but no link, when title optional

Issue #2937889 by larowlan, Sam152: Regression: LinkWidget no longer supports base fields with optional title

(cherry picked from commit 7871cc00)

Issue #2421001 by eiriksm, pfrenssen, YesCT, DuaelFr, gnuget, StryKaizer, Lendude, Jo Fitzgerald, andrewmacpherson, mgifford, geertvd, John Cook, mohit_aghera, Sinan Erdem, yoroy, thorandre, xjm, catch, joelpittet, idebr, alexpott, cilefen, dawehner, Cottser: Fix regression in the link widget where help text does not show

Issue #2613924 by heykarthikwithu, oknate, Mac_Weber, pguillard, attiks, aerozeppelin, claudiu.cristea, Prasun, alozie, lokapujya, Wim Leers: Link text isn't marked as required

Issue #2804391 by Berdir, Jo Fitzgerald, amateescu, gaurav.kapoor, arunkumark, wolffereast: Resaving menu links that points to a non-node entity changes the type to node and breaks the link

Issue #2776975 by joelpittet, dawehner, tim.plunkett, xjm, pfrenssen: March 3, 2017: Convert core to array syntax coding standards for Drupal 8.3.x RC phase

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2421021 by YesCT, lhuacho, martin107, shashikant_chauhan, amateescu, tremix: Missing help text for external url only for link widget

Issue #2423579 by mpdonadio, xjm, heilop, Wim Leers, webchick: Url::fromUrl('user-path:/') should throw an exception when a path component without a slash is given

Issue #2418017 by Wim Leers, YesCT, dawehner, webchick, jibran, amateescu, hussainweb: Implement autocomplete UI for the link widget

Issue #2417647 by Wim Leers, effulgentsia: Add leading slash to paths within 'user-path:' URIs, to allow 'user-path:' URIs to point to the <none> route

Issue #2418209 by chintan.vyas, lucastockmann: Replace user facing strings that use drupal.org as example of an external url

Issue #2416987 by YesCT, amateescu, webchick, Wim Leers, yched: Fix UI regression in the menu link form

Issue #2417793 by effulgentsia, Wim Leers, YesCT, yched, dawehner: Allow entity: URIs to be entered in link fields

Issue #2412509 by kgoel, pwolanin, Wim Leers, larowlan, effulgentsia, dawehner, xjm: Change LinkItem.uri to type 'uri' rather than 'string' and introduce user-path: scheme

Issue #2235457 by dawehner, amateescu, hussainweb, Berdir, benjy, Wim Leers, lokapujya, RavindraSingh, Ryan Weal, jibran, Jalandhar: Use link field for shortcut entity

Issue #2411143 by dawehner, effulgentsia, amateescu, larowlan: Change LinkItem schema to store URIs rather than URLs/paths/routes

Issue #2084987 by andypost, Jalandhar: Remove usage of field_ui_default_value and recommend proper replacement

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

Issue #2335659 by tim.plunkett, dawehner, effulgentsia, sun: Remove FormState ArrayAccess usage from core.

Issue #2308821 by tim.plunkett: Replace FormErrorInterface with $form_state->setErrorByName() and $form_state->setError().

Issue #2143291 by plach, alexpott, xjm, effulgentsia, pwolanin, swentel | yched: Clarify handling of field translatability.