Issue #2298001 by er.pushpinderrana | LewisNyman: Remove #page CSS from Seven.
Issue #2191543 by tim.plunkett: Fixed history_node_view_alter() overwrite all #attached on nodes.
Issue #2299499 by joshi.rohit100: Remove form_clear_error() as it is deprecated.
Issue #2300583 by larowlan: Consider adding larowlan and tim-e as contact module maintainers.
Issue #2287381 by alayham: Fixed views_ui dropbuttons display is not RTL friendly.
Issue #2273385 by damiankloip: Use a container parameter for the user tempstore expire time.
Issue #2284017 by t0xicCode: Fixed CamelCase FieldItemList preSave call.
Issue #2287777 by andypost: Optimize _dblog_get_message_types().
Issue #2035317 by andypost, hussainweb | dawehner: DateTimeDefaultWidget should implement ContainerFactoryPluginInterface.
Issue #2008616 by lokapujya, herom, kgoel | andypost: Convert user_uri() to $user->uri().
Issue #2010162 by tim.plunkett | InternetDevels: Convert node_uri() to $node->uri().
Issue #2242405 by mikebarkas, jlbellido | alexpott: Fixed FileTransfer::connect is protected yet the implementations are public and this is relied upon.
Issue #2279681 by mgifford, joshi.rohit100, thedavidmeister: Views' InOperator filter should use Unicode::truncate() in adminSummary().
Issue #2300611 by nickwaring89: Updating Custom Block module in MAINTAINERS.txt.
Issue #2272987 by followup sun: Fixed Do not persist session manager.
Issue #2257519 by sun, larowlan, xjm, cs_shadow: Move content assertion methods into a trait, so DUTB can consume it, too.
Merge branch '8.x' into 1498662-comment-subject