Issue #2225399 by marcvangend, yanniboi, mr.baileys, Wim Leers, visabhishek: Apply formatters and widgets to Feed base fields.
Issue #2159369 by ParisLiakos: Move aggregator_refresh() and most of ->removeItems() logic to a service.
Issue #2152673 by ParisLiakos: Remove duplicate edit route from aggregator and make delete/add consistent with rest of core.
Issue #1878302 by martin107, InternetDevels, nick_daffodil, chrisroane: Use 'delete' over 'remove' in the aggregator module.
Issue #1199946 by alexpott, fubhy, bojanz, steinmb, chx, catch: Fixed Disabled modules are broken beyond repair so the 'disable' functionality needs to be removed.
Issue #2074037 by Wim Leers, effulgentsia: Add drupalPostUrl() — drupalPost()/drupalPostAjax() are for forms only, D8 JS performs non-form HTTP requests.
Issue #293318 by alex_b, Berdir, rootatwc, Aron Novak, mustafau, akahn: Convert Aggregator feeds into entities.