Issue #2386571 by dawehner, hussainweb: Large array structures (e.g. $form) in stack trace results in huge memory usage in FlattenException::flattenArgs()
Issue #2207629 by droplet, tarekdj, Devin Carlson, rpayanm: Update matchMedia library to latest release
Issue #2368807 by yched: Remove special support for NULL values in FieldItemList
Issue #2393125 by hussainweb, droplet, mitrpaka, tarekdj: Update underscore and backbone library to latest release
Issue #2390691 by Wim Leers, Berdir, arlinsandbulte: Expose node grants as cache context
Issue #2393765 by alexpott: Several forms should use ConfigFormBase and not FormBase