The fields in ACF Block saved just fine, but anything inside the old Metabox won’t be saved to database.
I even tested it in fresh installation (WP 4.9.8 and PHP 7.0) without any other plugin except Gutenberg 4.0 and ACF 5.8.
Switching back to ACF 5.7 solves the issue so the bug is specific to ACF 5.8.
Anyone having this issue?
Yes, having the same issue! I posted about it in the ‘Private: Beta Testing’ forum but can’t follow any replies because I’m not a Beta Tester Member and the signup link don’t work: http://eepurl.com/hJCjw
¯\_(ツ)_/¯
The best way to submit bugs and get questions answered on a beta version is to contact support directly https://www.advancedcustomfields.com/contact/
I have the same problem, posts not saving…..metabox new data, just some old data…..