Issue #2123251 by Jelle_S, marcvangend, attiks, Sutharsan: Improve DX of responsive images; convert theme functions to new #type element

Issue #2349461 by Jelle_S, mdrummond, attiks, Wim Leers: Move fallback image style into the responsive image style entity

Issue #2321901 by JeroenT, epari.siva, unstatu, Temoor, lokapujya, LinL, pcambra, piyuesh23: Replace all instances of entity_load('image_style') and entity_load_multiple('image_style') with static method calls

Issue #2405469 by yched, googletorp, amateescu, larowlan, Berdir: FileFormatterBase should extend EntityReferenceFormatterBase

Issue #2383165 by sidharrell, alexpott: ResponsiveImageStyle config entities should depend on the image styles they use

Issue #2424697 by jedihe, dalguete, yched: ResponsiveImageFormatter throws an exception on node preview

Revert "Issue #2424697 by jedihe, yched: ResponsiveImageFormatter throws an exception on node preview"

This reverts commit a0d5bc00.

Issue #2260061 by Jelle_S, attiks, Wim Leers, mdrummond, mgifford, holist: Responsive image module does not support sizes/picture polyfill 2.2

Issue #2350837 by dawehner, Berdir, larowlan, Wim Leers: Convert most usages of EntityInterface::getSystemPath() to use routes

Issue #2322037 by oenie, Temoor, jepSter, rpayanm: Replace all instances of responsive_image_mapping_load(), entity_load('responsive_image_mapping') and entity_load_multiple('responsive_image_mapping') with static method calls.

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

Issue #2271529 by attiks, alexpott, Lowell, YesCT, Jelle_S | mdrummond: Move breakpoint settings to theme and module *.breakpoints.yml files at root level.

Issue #2204159 by Wim Leers, longwave, tim.plunkett: (Responsive) Image styles do not add correct cache tags, nor do they invalidate cache tags upon flushing.

Issue #2136197 by andypost, jessebeach, swentel, longwave, Berdir: Move field/instance/widget/formatter settings out of annotation / plugin definition.

Issue #2030653 by Eli-T, mike.davis, JayeshSolanki, Xano, JeroenT: Expand ResponsiveImageMapping with methods.

Issue #2124377 by ellishettinga, Jelle_S, attiks, mdrummond, Schnitzel, InternetDevels: Rename "Picture" module to "Responsive Image" module.

Issue #2203407 by nod_, sun: Replace #attached library array values with provider-namespaced strings.

Issue #2042773 by yched, Berdir, pcambra: Change #items within a theme_field() render array from an *array* to the same $items *object* used throughout the rest of the formatter pipeline.

Issue #2050835 by Berdir | yched: Move Widget, Formatter, and FieldType plugin types to the Core\Field system.

Issue #2051923 by Berdir, dixon_, plach: Rename \Drupal\Core\Entity\Field\Field, related subclasses and interfaces to *FieldItemList.

Issue #2021817 by effulgentsia, yched: Make widgets / formatters work on EntityNG Field value objects.

Issue #1969728 by yched, effulgentsia, swentel, fago, plach: Implement Field API 'field types' as TypedData Plugins.

Issue #1849752 by effulgentsia, Berdir, jibran, neclimdul: Abstract non-Drupal-specific parts of AnnotatedClassDiscovery into a Drupal\Component base class.