Issue #2667242 by Anul, felribeiro, eojthebrave, pranavbabbar: Use consistent terminology when referencing administration themes in the UI (not "admin theme")

Issue #2578519 by phenaproxima, webchick: Node has invalid config schema for node_unpublish_by_keyword_action

Issue #2459971 by Gábor Hojtsy: The langcode key on configuration files is not explicit in configuration schema

Issue #2324121 by Berdir, slashrsm, alexpott: Fixed NodeType's settings array was meant to be able to store information from mutliple modules.

Issue #2283977 by alexpott, Gábor Hojtsy, effulgentsia, fago: Create a new ConfigEntity type for storing bundle-specific customizations of base fields.

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 #2274175 by tim.plunkett, vijaycs85: Block plugin schema should be defined separately from the entity.

Issue #2268975 by Gábor Hojtsy, vijaycs85: Fixed named schema elements missing when installing Drupal.

Issue #2167623 by danilenko_dn, sidharthap, Nitesh Sethia, krishnan.n, aitiba, alexpott, ashwinikumar, Barrett, damiankloip, deepakaryan1988, foxtrotcharlie, ianthomas_uk, neetu morwani, nonsie, piyuesh23, Sharique, sivaji, sushantpaste, swentel, vijaycs85, YesCT: Add test for all default configuration to ensure schema exists and is correct.

Issue #2042807 by tim.plunkett, pwolanin, ianthomas_uk, jhodgdon: Convert search plugins to use a ConfigEntity and a PluginBag.

Issue #2053461 by larowlan, andypost, tim.plunkett, swentel: Node type settings such as published state, promoted state, create revision and author information cannot be turned off.