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

Issue #2901726 by mfernea, gmario, finn.lewis, robertoperuzzo, rachel_norfolk: Fix 'Squiz.Functions.MultiLineFunctionDeclaration' coding standard

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 #2502621 by Pravin Ajaaz, hussainweb, Peacog, jhodgdon, ivanjaros: Replace implement notes with inheritdoc tag

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

Issue #2340123 by Wim Leers: Setting cache tags can be tricky: use strings instead of nested arrays to improve DX.

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

Issue #1167248 by Berdir, damiankloip, Alan Evans, beejeebus, catch: Add CacheBackendInterface::setMultiple().

Issue #2227187 by Mykhailo Gurei, Jalandhar, cs_shadow, mandar.harkare | Berdir: Stop refering to config storage as storage controller.

Issue #2169447 by damiankloip, sun, longwave: DX: Supply CacheBackendInterface::CACHE_PERMANENT as Cache::PERMANENT.

Issue #2100329 by cosmicdreams: Use \Drupal instead of Drupal to make IDEs and static code analyse tools happy.

Issue #1971158 by Berdir, beejeebus, alexpott, amateescu: Follow-up: Add loadMultiple() and listAll() caching to (cached) config storage.

Issue #1971158 by Berdir, beejeebus, alexpott, amateescu: Add loadMultiple() and listAll() caching to (cached) config storage.