Issue #2432837 by Wim Leers, Fabianx: Make cache contexts hierarchical (e.g. 'user' is more specific than 'user.roles')

Issue #2421263 by alexpott, formatC'vt, kim.pepper, andypost, larowlan, chx: Potential data loss: concurrent (i.e. by different users) node edits leak through preview

Issue #2225427 by ianthomas_uk, martin107, JeroenT, LoMo: Remove remaining uses of deprecated language functions (mostly in object oriented code)

Issue #1510544 by swentel, Bojhan, Gábor Hojtsy, merlinofchaos, Cottser, Wim Leers, plopesc, aspilicious, sannejanssen,  larowlan, tim.plunkett, nod_: Fixed Show previews in front-end theme, able to select different view modes.

Issue #1316692 by tim.plunkett, dawehner: Convert hook_admin_paths() into declarative properties on routes.

Issue #2109035 by tim.plunkett, damiankloip, dawehner, chx: Make access checkers (much) easier to find.

Issue #2084279 by herom, andypost, David Hernández, dawehner, Xano: Remove plugin.manager.entity service in favor of entity.manager.

Issue #2089635 by tim.plunkett, disasm, larowlan: Convert non-test non-form page callbacks to routes and controllers.

Issue #2057869 by dawehner, jibran: Provide an alias for 'plugin.manager.entity' called 'entity.manager'.

Issue #1946434 by tim.plunkett: Convert all of confirm_form() in node.admin.inc and node.pages.inc to the new form interface.