Hello,
since this thread is closed:
i cannot post my solution there. I have found a way to modify custom text/tel objects to a half-sized text box.
You have to use the api to manipulate the custom field. There is an endpoint called “object_manager_attribute”. With a PUT-Request you can add the specific option “item_class”, where you can set the value to “formGroup–halfSize”.
Use it at your own risk, because you are manipulating objects on your system in a non-typical way!
Summary
First get the ID of your custom object by calling the Endpoint with a GET-Request. If you know the id, you can edit the object by sending a PUT-Request to /api/v1/object_manager_attribute/{id} with the following minimalistic payload:
{
"name": "phone2",
"object":"User",
"data_type": "input",
"data_option": {
"type": "tel",
"maxlength": 120,
"item_class": "formGroup--halfSize"
}
}
Then the text field is in half size like first name or last name.