The Message field allows a user to enter text in a textarea form field. This can be used to request users a detailed answer to your question.
To learn about the common settings that are applicable to all field types kindly refer to field settings doc
Below you will find details of additional settings that are particular to this field.
Besides the common settings, there are a few additional settings that are available for this field type only. These settings can be found under the "Field Settings" panel.
Minimum Length - You can restrict the input for a minimum number of characters using this option.
Maximum Length - Similarly you may also restrict it for maximum length in characters.
You can easily adjust the height of this input field by dragging up & down the bottom controller pointer.