Issue #2361757 by rpayanm: Remove usage of mime_header_encode().
Issue #2361711 by rpayanm: Remove usage of drupal_convert_to_utf8().
Issue #1948418 by webflo, martin107, galooph, cilefen, gaurav.goyal, amitgoyal, dawehner, dstol: Fixed Address SA-CONTRIB-2013-035 for views in D8.
Issue #2351589 by ultimike, penyaskito: Fixed Exception when a source has no destId.
Issue #2324371 by lauriii, aneek, chx, joelpittet, webflo, Fabianx, rteijeiro: Fix common HTML escaped render #key values due to Twig autoescape.
Issue #2353699 by jarsenx | ultimike: D6->D8 Migration missing variable: default_nodes_main.
Issue #2353667 by micnap | ultimike: D6->D8 Migration missing variable: forum_nav_vocabulary.
Issue #2363589 by wizonesolutions: Fixed Wrong Contains specification in \Drupal\contact\MessageInterface.
Issue #2362517 by Wim Leers: Improve default 403/404 exception HTML subscriber: don't duplicate the page render pipeline, use the routing system — add system.403 and system.404 routes.
Issue #2349615 by mortendk | davidhernandez: Copy aggregator templates to Classy.
Issue #2349771 by lauriii | davidhernandez: Copy user templates to Classy.
Issue #2349731 by lauriii | davidhernandez: Copy search templates to Classy.
Issue #2349727 by cilefen, Xen | davidhernandez: Copy rdf templates to Classy.
Issue #2355239 by kgoel | dawehner: Let AggregatorItemViewsData and AggregatorFeedViewsData use EntityViewsData.
Issue #2349675 by mortendk, emma.maria | davidhernandez: Copy file templates to Classy.
Issue #2363139 by Wim Leers, dawehner, larowlan: _content controllers may only return render arrays, not strings.
Issue #2221577 by andypost, alexpott, yched: Fix assumption that field settings is not a nested array.
Issue #2359879 by penyaskito, Gábor Hojtsy: Fixed Session negotiation settings cannot actually be changed on the UI.
Issue #2363741 by joelpittet: Upgrade Twig to 1.16.* from 1.15.*.
Issue #2039709 by dawehner, swentel, MantasK | jurcello: Fixed Forward slash in filter aliases in url alias overview doesn't work.