Advanced Custom Fields Pro 6.2.9

Fix - Added missing function register_field_group().
Fix - Fixed PHP 5.4 error "Can't use function return value in write context".
Fix - Fixed bug causing wp_options values to be slashed incorrectly.
Fix - Fixed bug where "sync" feature imported field groups without fields.
Fix - Fixed bug preventing get_field_object() working with a field key.
Fix - Fixed bug causing incorrect results in get_sub_field().
Fix - Fixed bug causing draft and preview issues with serialized values.
Fix - Fixed bug causing reversed field group metabox order.
Fix - Fixed bug causing incorrect character count when validating values.
Fix - Fixed bug showing incorrect choices for post_template location rule.
Fix - Fixed bug causing incorrect value retrieval after switch_to_blog().
i18n - Updated Persian translation thanks to Majix.

New - Added support for persistent object caching.
Fix - Fixed PHP error in determine_locale() affecting AJAX requests.
Fix - Fixed bug affecting dynamic metabox check when selecting "default" page template.
Fix - Fixed bug where tab fields did not render correctly within a dynamic metabox.
Tweak - Removed language fallback from "zh_TW" to "zh_CN".
Dev - Refactored various core functions.
Dev - Added new hook variation functions acf_add_filter_variations() and acf_add_action_variations().
i18n - Updated Portuguese language thanks to Pedro Mendonça.
i18n - Updated German translation thanks to Ralf Koller.
i18n - Updated Swiss German translation thanks to Raphael Hüni.

Fix - Fixed bug preventing metaboxes from saving if validation fails within Gutenberg.
Fix - Fixed bug causing unload prompt to show incorrectly within Gutenberg.
Fix - Fixed JS error when selecting taxonomy terms within Gutenberg.
Fix - Fixed bug causing jQuery sortable issues within other plugins.
Tweak - Improved loading translations by adding fallback from region to country when .mo file does not exit.
Tweak - Improved punctuation throughout admin notices.
Tweak - Improved performance and accuracy when loading a user field value.
Dev - Added filter 'acf/get_locale' to customize the locale used to load translations.
Dev - Added filter 'acf/allow_unfiltered_html' to customize if current user can save unfiltered HTML.
Dev - Added new data storage functions acf_register_store() and acf_get_store().
Dev - Moved from .less to .scss and minified all css.
i18n - Updated French translation thanks to Maxime Bernard-Jacquet.
i18n - Updated Czech translation thanks to David Rychly.