Field groups

Hi,

The UM documentation mentions field groups :

Form elements
The form builder contains several different elements that you can use to build your forms. These include master rows, sub rows, columns, field groups, fields, separators, dividers, spacing and text blocks.

Where can I activate this ? How can I create a group ?
I can’t seem to find it anywhere in the form editor…

Thanks again for this great plugin !
Yan.

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