Issue #2454649 by Aki Tendo, dawehner: Cache Optimization and hardening -- [PP-1] Use assert() instead of exceptions in Cache::merge(Tags|Contexts)

Issue #2575615 by alexpott, pwolanin, stefan.r, catch, dawehner, effulgentsia, xjm, David_Rothstein, iMiksu, lauriii, joelpittet: Introduce HtmlEscapedText and remove SafeMarkup::setMultiple() and SafeMarkup::getAll() and remove the static safeStrings list

Issue #2576533 by alexpott, stefan.r, Wim Leers, dawehner, xjm, effulgentsia, catch: Rename SafeStringInterface to MarkupInterface and move related classes

Issue #2571695 by dawehner, plach, stefan.r, jaredsmith, lauriii, YesCT, xjm, catch, alexpott, joelpittet, Ryan Weal, Sutharsan, subhojit777, justAChris, nlisgo, effulgentsia, rpayanm, larowlan, chx, geertvd: Remove !placeholder and unsafe string return from SafeMarkup::format()

Issue #2485513 by Xano, tstoeckler, lauriii: DefaultFactory cannot deal with objects as plugin definitions

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

Issue #2559971 by stefan.r, alexpott, lauriii, nlisgo, plach, dawehner: Make SafeMarkup::format() return a safe string object to remove reliance on a static, unpredictable safe list

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

Issue #2509218 by plach, stefan.r, pwolanin, effulgentsia, dawehner, jhedstrom, almaudoh, Wim Leers, subhojit777, iMiksu, alexpott, catch, xjm, lauriii, joelpittet, Cottser: Ensure that SafeString objects can be used in non-HTML contexts

Issue #2565895 by dawehner, stefan.r, googletorp, effulgentsia, lauriii, jcnventura, David_Rothstein, catch, xjm, joelpittet, pwolanin, plach, larowlan, cilefen: Add a new :placeholder to SafeMarkup::format() for URLs that handles bad protocols

Issue #2545972 by alexpott, joelpittet, ericjenkins, stefan.r, Wim Leers, Cottser: Remove all code usages SafeMarkup::checkPlain() and rely more on Twig autoescaping

Issue #2554889 by Berdir, Cottser, Daniel_Rose, JeroenT, RavindraSingh, Wim Leers, YesCT, akalata, alexpott, alimac, aneek, catch, cdulude, chx, cilefen, cmanalansan, crowdcg, cwells, davidhernandez, dawehner, dtraft, effulgentsia, harjotsingh, hass, ianthomas_uk, joelpittet, josephdpurcell, justAChris, kbaringer, lauriii, lduerig, leslieg, lokapujya, mpdonadio, peezy, pwolanin, realdream, sclapp, stefan.r, tim.plunkett, webchick, xjm: Remove SafeMarkup::set() from the codebase.

Issue #2549393 by alexpott, dawehner, lauriii, andypost, xjm: Remove SafeMarkup::escape() and rely more on Twig autoescaping

Issue #2559969 by alexpott: Make SafeStringInterface extend \JsonSerializable so we don't have to do so much string casting

Issue #2558179 by jhedstrom, dawehner, catch: Database dump script produces a dump with syntax errors in it

Issue #2555565 by darol100: Fix typo in core/tests/Drupal/Tests/Component/DependencyInjection/Dumper/OptimizedPhpArrayDumperTest.php

Issue #2552579 by alexpott: Remove SafeMarkup::placeholder(), deprecate drupal_placeholder() and stop drupal_placeholder() from marking safe

Issue #2497243 by Fabianx, znerol, fgm, Wim Leers, darol100, jhedstrom, hussainweb, pfrenssen, neclimdul, jibran, Nitesh Sethia, dawehner, chx, catch, benjy, Aki Tendo: Replace Symfony container with a Drupal one, stored in cache

Issue #2550055 by geertvd, alexpott: Remove SafeMarkup::replace() and use ViewsRenderPipelineSafeString instead

Issue #2549791 by alexpott, Wim Leers: Remove SafeMarkup::xssFilter() and provide ability to define #markup escaping strategy and what tags to filter

Issue #2551335 by alexpott, Wim Leers: Remove unnecessary SafeMarkup usage in tests and clear the static cache before every run

Issue #2408013 by Aki Tendo, alexpott, Fabianx, dawehner, Crell, jhodgdon, Wim Leers, aspilicious: Adding Assertions to Drupal - Test Tools

Issue #2506195 by alexpott, joelpittet, xjm, David_Rothstein, Fabianx, pwolanin: Remove SafeMarkup::set() from Xss::filter()

Issue #2408371 by dawehner, Fabianx, alexpott, bforchhammer: Proxies of module interfaces don't work

Issue #1392754 by tss, justAChris, jhodgdon: Comply with new documentation standards for @file for namespaced class files

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 #2506133 by alexpott, joelpittet, dawehner, pwolanin: Replace SafeMarkup::set() in \Drupal\Core\Template\Attribute

Issue #2273925 by larowlan, aneek, lauriii, mikey_p, joelpittet, dimaro, Fabianx, xjm, jaredsmith, effulgentsia, lokapujya, iMiksu, chx, YesCT, googletorp, dawehner, Wim Leers, Cottser: Ensure #markup is XSS escaped in Renderer::doRender()

Issue #2491155 by mikeburrelljr, Mac_Weber, opdavies: Update drupal.org and kernel.org URLs in core modules (Follow-up to 2489912)

Issue #2395143 by amateescu, Fabianx, Berdir, beejeebus, dashaforbes, alexpott, larowlan, znerol, dawehner, catch, neclimdul, yched, fgm, effulgentsia: YAML parsing is very slow, cache it with FileCache