Hi all,
WP 5.0 with Classic Editor 1.0 Installed is causing a WSOD (White Screen of Death) when editing field groups.
To fix: Go to Settings > Writing and then set “Default editor for all users” to “Classic Editor” and “Allow users to switch editors” to “No”.
Please follow the full discussion with plugin developers here: https://wordpress.org/support/topic/classic-editor-is-blank-in-wordpress-5-0/
Thanks
Elliot