Issue #2809237 by dmitryl, alexpott, iampuma, muschpusch, louisnagtegaal, twfahey, aburrows, Mike Lewis, nickmans, borisson_, jcnventura: Properly deprecate AllowedTagsXssTrait

Issue #2806651 by stmh, muschpusch, ifrik, tim.plunkett, msti, SenneS: Replace "Delete" block on the block-layout page with "Remove"