Issue #3415938 by longwave, Spokje, taraskorpach: Remove ContainerAwareTrait from CacheFactory and ChainedFastBackendFactory

Issue #2662844 by gapple, yogeshmpawar, penyaskito, dawehner, catch, smustgrave, alexpott, chx: cache.backend.chainedfast misbehaves when both fast and consistent backends point to the same storage

Issue #3222251 by bbrala, longwave: [November 8, 2021] Replace all isset constructs with the null coalescing operator

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 #2783393 by Mile23: Fix 'Drupal.Commenting.FunctionComment.IncorrectParamVarName' coding standard

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

Issue #2248767 by effulgentsia, beejeebus, alexpott: Use fast, local cache back-end (APCu, if available) for low-write caches (bootstrap, discovery, and config).

Issue #2231595 by beejeebus, Steven Merrill, kim.pepper, Wim Leers, msonnabaum: Add a cache backend that checks an inconsistent cache, then falls back to a consistent cache backend.