Hi @dennis
Could you please tell me the PHP version you have? Also, could you please share your code the steps to reproduce the error message (such as adding the custom field or adding a new row)?
The problem is that I couldn’t reproduce the message on my end using the repeater field. I believe the plugin author doesn’t use the isset() function because $field['collapsed'] should always be set when it’s called. It’s possible that your code doesn’t set this variable so PHP returned the error.
I hope this makes sense. Thanks!
