"tag" not working with grouped schema

[webdevnerdstuff]

Node: version 8.9.0
VGG: version 2.1.1

Problem
Adding tag="div" still uses fieldset when the schema has grouped fields.

Example:

<vue-form-generator 
 :model="model" 
 :schema="fields" 
 :options="formOptions" 
 ref="someForm" 
 tag="div" 
 >
 </vue-form-generator>

This works with a regular schema.

Ex. (works)

schema: {
    fields: [
        {
            type: 'input',
            inputType: 'input',
            label: 'First Name',
        },
        {
            type: 'input',
            inputType: 'input',
            label: 'Last Name',
        },
    ],
}

With a grouped schema it does not work.

Ex. (does not work)

schema: {
    groups: [
        {
            fields: [
                {
                    type: 'input',
                    inputType: 'input',
                    label: 'First Name',
                },
            ],
        },
        {
            fields: [
                {
                    type: 'input',
                    inputType: 'input',
                    label: 'Last Name',
                },
            ],
        },
    ],
}

Expected Outcome
When adding tag to VFG and having grouped fields, it will change fieldset to the tag specified.

[webdevnerdstuff]

Awesome. Thank you!

[gezichenshan]

Where can I read the documentation about tag?