Issue #2568247 by heddn, anavarre, gapple, mstrelan, Cottser, dawehner, joelpittet, alexpott, hoff331: Remove the Twig C extension requirement as it needs to be proven it's still relevant for modern PHP versions

(cherry picked from commit fb8cdd46)

Issue #2762549 by alexpott: Part 2: Array was modified by the user comparison function in ConfigDependencyManager::getDependentEntities()

(cherry picked from commit 2c3d5ecb)

(cherry picked from commit 5c4f93fd)

(cherry picked from commit 46efe012)

Issue #2738891 by martin107, rashid_786, Wim Leers, remydenton: Instructions for adding CKEditor stylesheets are outdated

(cherry picked from commit 4e9ed76c)

Issue #1266748 by swentel, Berdir, jcnventura, arlinsandbulte, yched, droplet, amateescu: Changing cardinality lower than highest existing delta causes data loss upon save

(cherry picked from commit a1b02adf)

(cherry picked from commit eadde8da)

Issue #2675648 by Bès, Haza, dawehner, chx: Code after hook_link_alter() invocation does not use the altered data

Issue #2698811 by danmuzyka, Wim Leers, jhedstrom, Fabianx: BigPipe unnecessarily renders and sends multiple-occurrence placeholders multiple times when using JS — can cause JS errors

(cherry picked from commit 5e86905f)

Issue #2757427 by alexpott, Xano: Array was modified by the user comparison function in ConfigDependencyManager::getDependentEntities()

(cherry picked from commit 3eb2def4)

(cherry picked from commit 9a0f369b)

Issue #2744421 by andypost, Wim Leers: QueryArgsCacheContext::getContext() may return NULL, violates the interface

(cherry picked from commit 63b7ded4)

(cherry picked from commit ea6a8c33)

Issue #2754477 by alexpott, jonathan1055, mr.baileys, swentel: Unexpected config entity delete due to dependency calculations

Issue #2750941 by dawehner, klausi, jibran: Additional BC assertions from WebTestBase to BrowserTestBase

(cherry picked from commit c9fb29d5)

(cherry picked from commit 2125663d)

Revert "Issue #2664530 by Lendude: Views Combined fields filter with "Contains any word"  or "Contains all words" operator results in an incorrect SQL query and a fatal error"

This reverts commit 574487f5.

Issue #2657110 by claudiu.cristea: ResponsiveImageFormatter should define dependencies to responsive image style entity

(cherry picked from commit f7584f7617202321e9bbaeb73b6c85dfc88d2eec)

Issue #2752315 by Eric_A, pfrenssen, RoySegall: Fix visibility of AssertLegacyTrait::assertNoEscaped()

Revert "Issue #2675010 by hchonov: Cloned entity will point to the same field objects if the clone was created after an entity translation has been initialized"

This reverts commit 5e942cff.

Issue #2698083 by quietone, Sam152, Mac_Weber, vasi: D6->D8: Migrating links without leading slash leads to fatal error

(cherry picked from commit d8d92b59)

Issue #2664530 by Lendude: Views Combined fields filter with "Contains any word"  or "Contains all words" operator results in an incorrect SQL query and a fatal error

(cherry picked from commit a64ea9d3)

Issue #2751583 by tstoeckler: Entity::urlRouteParameters() calls getRevisionId() for non-revisionable entities

(cherry picked from commit 8ce4b6bc)

Issue #2751121 by tstoeckler, kiamlaluno: class StatusMessages documentation page contains incorrect markup

(cherry picked from commit 90b986b0)

(cherry picked from commit b6c18664)

Issue #2687003 by alexpott, mikeryan, eojthebrave, xjm, benjy, quietone, catch: Update migrate.api.php to reflect the current API

(cherry picked from commit 0bbcdf46)

(cherry picked from commit c0094422)

Issue #2735199 by klausi, naveenvalecha, Eric_A, dawehner, jhodgdon: Convert web tests to browser tests for help module

Issue #2752127 by jalpesh, Eric_A: drupal/core-assertion is missing from the drupal/core replace section

(cherry picked from commit 9e73da7b)

Issue #2700581 by mikeryan, benjy, heddn, vasi: Destination bundle set in destination plugin, not in process

(cherry picked from commit a3947a93)

Issue #2384459 by mikran, mbovan, slashrsm, chx, Berdir, yched: Add entity query condition for delta in EFQ

(cherry picked from commit 71094542)

Issue #2499239 by Mile23, neclimdul, alexpott, jhedstrom, Mixologic, Crell, Xano, dawehner: Use test suite classes to discover different test types under phpunit, allow contrib harmony with run-tests

(cherry picked from commit 765aa9e7)

Issue #1390580 by mohit_aghera, heliogabal, Chernous_dn, andrewmacpherson, mgifford, droplet, Everett Zufelt: Add comments for skip link and main-content anchor in templates

Issue #2684213 by amateescu, larowlan, josephdpurcell, dawehner: Preview on forward node revisions throws an error

(cherry picked from commit c5bfca64)