Upgrade from Divi Breeze

"Divi Sync" is designed to work with Divi 4 Theme Builder header and footer.

For upgrade purposes files can be downloaded and imported via Divi -> Theme Builder. 
https://dashboard.cmsbased.net/dl.php?type=d&id=82

"Divi Helper" WordPress Plugin is required to provide API endpoints with "Theme Builder" template content. 

https://dashboard.cmsbased.net/dl.php?type=d&id=83