SA-CORE-2019-002 by greggles, cashwilliams, EclipseGc, larowlan, samuel.mortenson, alexpott, tedbow, effulgentsia, Fabianx, xjm, mlhess

Issue #2955457 by pfrenssen, Chewie, unrealauk, alexpott, Pol: ConfigFactory static cache gets polluted with data from config overrides

Issue #3020142 by mglaman, tim.plunkett: Test module no_transitions_css has invalid hook_page_attachments

(cherry picked from commit c00be4c4)

Issue #3007973 by tim.plunkett, lukasss, xopoc, bnjmnm, stompersly: Layout builder prevents the rendering of extra fields (like Links) on pages not using Layout Builder

(cherry picked from commit fea6c512)

(cherry picked from commit 95b3b178)

Issue #2845975 by quietone, Jo Fitzgerald, aleevas, maxocub, Gábor Hojtsy: Migrate Drupal 6 user profile field value option translations

(cherry picked from commit 75a42131)

Issue #2701829 by alexpott, andypost, Soul88, Graber, Eduardo Morales, dawehner, pingwin4eg, catch, Berdir, jibran, httang12: Extension objects should not implement \Serializable

Issue #2693727 by mikelutz, sanduhrs, CalebD, ajlib, Lendude, tstoeckler, catch: Limiting options for exposed Language filters causes errors and doesn't work for special languages

(cherry picked from commit 0b6c398e)

Issue #3018942 by welly, alexpott, jibran, Krzysztof Domański, floydm: Domain URL language detection - InvalidArgumentException: The user-entered string must begin with a '/', '?', or '#'

(cherry picked from commit 79e94b49)

(cherry picked from commit 60574dd0)

Issue #3022183 by wengerk, benjifisher: Fix BlockContentAccessHandlerTest::providerTestAccess wrong coverage by early return

(cherry picked from commit 30fb2237)

Issue #2984072 by vijaycs85, Lendude, ApacheEx, dawehner: System: Convert ErrorHandlerTest to phpunit

(cherry picked from commit bda5967e)

Issue #3007439 by tim.plunkett, Wim Leers, xopoc: Layout builder renders Book navigation block on non-book pages

(cherry picked from commit 8bf6ee38)

Issue #2927768 by justinlevi, Lendude, pritish.kumar, Wim Leers, dawehner: Update RestRegisterUserTest to use the ResourceTestBase base class instead of the deprecated RESTTestBase

(cherry picked from commit 47817754)

Issue #2865344 by mpdonadio, Lendude, mbovan, organicwire, alexpott, jibran, jhedstrom, bobemoe, Berdir, larowlan: Exposed date filters 'empty' and 'not empty' are broken

(cherry picked from commit 8e3bcf48)

Issue #2974274 by mitrpaka, RumyanaRuseva, joachim: exception message for unrecognized source IDs in lookupDestinationIds() should have more detail

(cherry picked from commit aa577bef)

Issue #2809305 by Upchuk, Pavan B S, Jo Fitzgerald, tim.plunkett, Berdir: Block Context assignment form element shows even if no options are available

(cherry picked from commit 55f13aac)

Issue #3018539 by phenaproxima, rodrigoaguilera, alexpott: Media types cannot be created in the UI without JavaScript

(cherry picked from commit 3ba6bc11)

Issue #3018764 by Wim Leers: One test case in MediaUiFunctionalTest is not actually tested due to a duplicate key

(cherry picked from commit 52901b5f)

(cherry picked from commit f7f07d81)

Issue #2883553 by govind.maloo, msankhala, seanB, Berdir, xjm, alexpott: Obsolete argument for hasPermission in node_node_access()

(cherry picked from commit 269c716d)

(cherry picked from commit 2b511ec3)

Issue #2956368 by marcoscano, Nitebreed, ph53: MediaThumbnailFormatter produces unhelpful text alternative and title attributes for media thumbnails

(cherry picked from commit e6dfd046)

Issue #3000240 by govind.maloo, philipnorton42, msankhala, izus, scott_euser, joachim, alexpott, catch: hook_user_format_name_alter() should document that it's invoked for both user entities and session objects

(cherry picked from commit b6208e52)

Issue #2977276 by Sam152, ergonlogic, amateescu, jibran, catch, greggmarshall: Node views integration that joins revisions to the default entity fails to consider langcode, resulting in duplicate rows

(cherry picked from commit 30cfcd03)

Issue #2511968 by Berdir, jhedstrom, zaporylie, catch, dawehner, alexpott, amateescu: Path field should fall back to language neutral aliases (also makes this happen for the form widget!)

(cherry picked from commit 7758b755)

Issue #2737741 by amateescu, anoopjohn: Drupal\menu_link_content\Plugin\Menu\MenuLinkContent::getUuid() does not return any value

(cherry picked from commit 39f95a14)

Issue #2370115 by Upchuk, nafsinvk, jibran: Clicking 'Add to shortcuts' adds shortcut multiple times

(cherry picked from commit edfd5bbe)

Issue #2968139 by tim.plunkett, tedbow: Layout Builder field blocks show up on Block UI when they shouldn't

(cherry picked from commit 87646bb8)

Issue #2911149 by quietone, Jo Fitzgerald, heddn, cogent, mikelutz: FormatDate process plugin doesn't handle zero values

(cherry picked from commit 0b2393d8)

Issue #3015110 by pwolanin, mikelutz, YesCT, quietone: migrate source plugin SqlBase::initializeIterator fails to update rows when high water reset to NULL or 0 and mapJoinable() = TRUE

(cherry picked from commit 978c9e1c)

Issue #3015004 by tedbow, andrewmacpherson, tim.plunkett: Distinguish between the repeated text of remove-section buttons in Layout Builder UI

(cherry picked from commit 23d304ff)

Issue #2936360 by tim.plunkett, samuel.mortenson: Remove duplicate references to the "layout_builder__layout" field from Layout Builder

(cherry picked from commit a4c915aa)

Issue #2924218 by amateescu, Fabianx: Clearing the persistent entity cache every time we switch between workspaces is super wasteful

(cherry picked from commit bd583a84)

Issue #2948068 by drpal, dawehner, borisson_, ethomas08, lauriii, yoroy, tedbow: Placing and then removing a block appends incorrect query string destination parameter

(cherry picked from commit 44664acf)

Issue #2936032 by gambry, nlisgo, alexpott, cwells, cilefen, Darvanen, DamienGR: Sites named with special characters cannot send mail

(cherry picked from commit 53c24728)

Issue #2894193 by alexpott, jlscott, kkonuhov, mallezie, larowlan: Multiple file upload does not validate extensions correctly

(cherry picked from commit 2b94ed3c)

Issue #3014772 by kiamlaluno: ModuleHandlerTest::testUninstallProfileDependency() uninstall a module and reports another module has been uninstalled

(cherry picked from commit 0a3f9f1a)

Revert "Revert "Issue #2809533 by Lendude, jibran: Convert AJAX part of \Drupal\system\Tests\Ajax\FrameworkTest to JavascriptTestBase""

This reverts commit e294daf3.