Issue #3113876 by Hardik_Patel_12, himmatbhatia, jungle, klausi, longwave: The "Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent::getException()" method is deprecated since Symfony 4.4, use "getThrowable()" instead

Issue #2920001 by Wim Leers, dawehner, borisson_, aheimlich, davidwbarratt: Add cacheable HTTP exceptions: Symfony HTTP exceptions + Drupal cacheability metadata

Issue #2825347 by Wim Leers: 'Accept' header still is used for determining response format of error responses, ?_format= has no effect AND serialization module's exception subscriber does not support status code 500 error responses

Issue #2838949 by damiankloip: HttpException Handling Does Not Pass Headers to Responses — results e.g. in missing Allow header for 405 responses

Issue #2739617 by dawehner, Wim Leers, neclimdul, chx: Make it easier to write on4xx() exception subscribers

Issue #2813755 by Wim Leers, dawehner, tedbow, damiankloip: JSON responses encoded inconsistently: make them all RFC4627-compliant

Issue #2659070 by Wim Leers, dawehner, tic2000, Crell: REST requests without Content-Type header: unhelpful response significantly hinders DX, should receive a 415 response

Issue #2403307 by dawehner, marthinal, tedbow, clemens.tolboom, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authentication: log in, check login status, log out

Revert "Issue #2403307 by dawehner, marthinal, tedbow, clemens.tolboom, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authentication: log in, check login status, log out"

This reverts commit 18feefc3.

Issue #2403307 by dawehner, marthinal, tedbow, clemens.tolboom, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authentication: log in, check login status, log out

Revert "Issue #2403307 by dawehner, marthinal, clemens.tolboom, tedbow, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authenication: log in, check login status, log out"

This reverts commit da16ae56.

Issue #2403307 by dawehner, marthinal, clemens.tolboom, tedbow, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authenication: log in, check login status, log out

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2472323 by dawehner, neclimdul, Crell, kim.pepper, nod_, Wim Leers, larowlan, jibran, pwolanin, catch: Move modal / dialog to query parameters

Issue #2372011 by richardcanoe, Noe_: NotFoundHttpException handler should take into account it's parameters