Issue #2853503 by Aki Tendo, alexpott, larowlan, Wim Leers, klausi, fgm, dawehner, mondrake, catch, Berdir, neclimdul, borisson_: Remove all assert('string') calls from Drupal core because deprecated in PHP 7.2

Issue #2837013 by benjifisher, leslieg, alexpott: clean_class Twig filter does not work with Views rewriting

Issue #2776975 by joelpittet, dawehner, tim.plunkett, xjm, pfrenssen: March 3, 2017: Convert core to array syntax coding standards for Drupal 8.3.x RC phase

Issue #88183 by Wim Leers, ahoeben, brianV, alexpott, kylebrowning, marvil07, chx, twistor, dawehner: Relative URLs in feeds should be converted to absolute ones

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2571845 by drupal.ninja03, hussainweb, anil280988, snehi, jhodgdon, GoZ, stefan.r: Links to wikipedia/php.net should be part of the actual t() string so they can be localized

Issue #2549077 by pwolanin, Wim Leers, phenaproxima, lauriii: Allow the "Limit allowed HTML tags" filter to also restrict HTML attributes, and only allow a small whitelist of attributes by default

Issue #2511306 by ElusiveMind, JeroenT, leolando.tan: Error: Call to a member function getElementsByTagName() in filter.module

Issue #2541102 by dawehner, hussainweb, John Cook, cilefen, joshi.rohit100, Fabianx: Get rid of strtr in Html::cleanCssIdentifier

Issue #1305882 by dawehner, nod_, Fabianx, Steven Jones, sun, nlisgo: drupal_html_id() considered harmful; remove ajax_html_ids to use GET (not POST) AJAX requests

Issue #2454447 by andypost, dawehner, rteijeiro: Split Utility\String class to support PHP 7 (String is a reserved word)

Issue #2121713 by tim.plunkett, dawehner, rteijeiro, jiv_e: Move drupal_html_id() and drupal_html_class() to Drupal\Component\Utility.