Issue #2711537 by chgasparoto, kostyashupenko: Syntax errors (un-quoted or mis-quoted strings) in various code examples in docs

Issue #2709411 by dagmar, jhodgdon: t() is used in an inconsistent way on Drupal\Core\Render\Element documentation

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

Issue #2560137 by dawehner, pwolanin, klausi, tsphethean, sun: Posting an array as value of a form element is allowed even when a string is expected (and bypasses #maxlength constraints) - first step: text fields

Issue #2226863 by cs_shadow, filijonka, joelpittet, pguillard: Update stale references to theme functions that have been converted to Twig