October v.3 AJAX request is sent twice

Using this documentation, I noticed that the Ajax request is sent twice.

OctoberCMS v3

Using the following configuration, the submission is only sent once:

    label: Content
    type: textarea
    size: small
    changeHandler: onChangeContent

I was unable to replicate this issue. If it is still a problem, feel free to contact the help desk: Contact Us - October CMS