cms-token and other cms tags are now enabled by default. This is bumped to 3.6 to signal to update the webcomponents module to 3.6 which has a significant default performance boost as well as numerous UX / a11y updates in HAX itself.
PHP 7.4 compatibility, improved Drupal 9 compatibility, when serving all JS from CDN, the CKEditor JS is now automatically exempted, and hardened against a very obscure edge case!