I’m having the same issue.
Illegal string offset ‘acfcloneindex’ …/advanced-custom-fields-pro/pro/fields/repeater.php:156
Invalid argument supplied for foreach() …/advanced-custom-fields-pro/pro/fields/repeater.php:255
Array to string conversion …/advanced-custom-fields-pro/pro/fields/repeater.php:156
This uses some repeater fields (that are obviously the problem) divided into tabbed sections.
I’m using 5.1.9.1
