Issue #2920678 by phenaproxima, Wim Leers, dawehner, Gogowitsch, Sam152, dww, longwave, yogeshmpawar, alexpott, borisson_, tstoeckler, jibran, amateescu, larowlan, tedbow: Add config validation for the allowed characters of machine names

Issue #2946 by chx, michaellenahan, jcnventura, quietone, ifrik, wengerk, AaronBauman, salvis, pplantinga, sun, David_Rothstein, tatarbj, alexpott, Wim Leers, iMiksu, vijaycs85, anoopjohn, nedjo, Owen Barton, bjaspan, soxofaan, Gogowitsch, raman.b, robeano, deepakrmklm, bleen, xmacinfo, catch, beginner, dww, Gábor Hojtsy, webchick, Dries, larowlan, snufkin, RobRoy, bdragon, wizonesolutions, Lendude, sokru: Login fails and no warning is issued if cookies are not enabled

Issue #2693485 by juhog, paulocs, Gogowitsch, Hardik_Patel_12, YesCT, Mirroar, Lal_, ravi.shankar, abhisekmazumdar, tim.plunkett, longwave, esolitos, TravisCarden, lapek, jhuhta, adriancid, samiullah, adalbertov, cilefen, mohit1604, Abhijith S, John Cook, alexpott, dawehner, pameeela, larowlan, catch, leisurman: Content types are ordered by machine name on /node/add page (+ similar issues with other entities)

Issue #2223967 by jofitz, LKS90, AdamPS, sja112, shaktik, pminf, Berdir, mxr576, bmcclure, Manuel Garcia, naveenvalecha, Gogowitsch, andypost, alexpott, jonathanshaw, claudiu.cristea, greggles: Do not decode a contact message twice

Issue #3108803 by k4v, ifrik, Gogowitsch: Error "default.settings.php should not be changed" during install

Issue #2507235 by Gogowitsch, ckaotik, Arla, tstoeckler, Berdir, Gábor Hojtsy: EntityType::getLowercaseLabel() breaks translation

Issue #82571 by asvira, Gogowitsch, flk, tstoeckler: Error message in installer mentions possibly wrong username, etc. but not port

Issue #3046298 by Gogowitsch, voleger, jhedstrom, larowlan: DX: tell developer which yaml file caused a ParseException

Issue #2784015 by amateescu, jlbellido, Gogowitsch, krknth, ibustos: Widget validation crashes on ItemList violations for widgets with a custom errorElement() implementation