Issue #3113971 by Spokje, mondrake, acbramley, phenaproxima, andypost, murilohp, mpdonadio, ravi.shankar, pavnish, pifagor, vladbo, JeroenT, voleger, Taran2L: Replace REQUEST_TIME in services

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

Revert "Issue #3055443 by alexpott, amateescu, catch, Berdir, chr.fritsch: Switch to a memory backend for running the database updates"

This reverts commit c22202ec.

Issue #3055443 by alexpott, amateescu, catch, Berdir, chr.fritsch: Switch to a memory backend for running the database updates

Issue #3031775 by singhkiran, Chi: Cache backend classes reference non-existing functions cache_get() and cache_get_multiple()

Issue #2853503 by Aki Tendo, alexpott, larowlan, Wim Leers, klausi, fgm, dawehner, mondrake, catch, Berdir, neclimdul, borisson_: Remove all assert('string') calls from Drupal core because deprecated in PHP 7.2

Issue #2538956 by HeyLodyM, Wim Leers: Document that MemoryBackend::prepareItem()/::set() uses unserialize()/serialize() to break references

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 #2834580 by Berdir: Move locale.translation_status state key to a separate key/value collection

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 #2454649 by Aki Tendo, dawehner: Cache Optimization and hardening -- [PP-1] Use assert() instead of exceptions in Cache::merge(Tags|Contexts)

Issue #2501117 by catch, olli, Wim Leers, dawehner: Add static caching for PermissionsHashGenerator::generate()

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

Issue #2459155 by alexpott, pfrenssen, hussainweb, neclimdul: Remove REQUEST_TIME from bootstrap.php

Issue #2411689 by alexpott: Use a MemoryBackend in StorageComparer so that configuration import validators don't have to reread data from disk or the db

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

Issue #2293163 by Wim Leers, pwolanin: Fixed MemoryBackend's cache entries may be modified unintentionally thanks to object references.

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

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

Issue #1858616 by Berdir: Extract generic CacheCollector implementation and interface from CacheArray.

Issue #1167144 by chx, catch, claudiu.cristea: Make cache backends responsible for their own storage.

Issue #1808112 by sun: Fixed Missing method visibility, bogus phpDoc and coding style in Cache backend classes.

Issue #1393392 by c960657, fubhy: Convert prefix cache clears to cache tags, then remove support for them.