textarea as auto fitting pdf-TextField

[OmitLeChuck]

I've already looked around a bit on google and so on, but haven't found a working solution as to how I could create a field that automatically adjusts the font size when the text is larger than the field itself, as is the case in some PDF-files.

I've already gone down the (code)rabbit hole and came across the following function:

protected function _tag_open_TEXTAREA($param)

I suspect that this is the right place to start, but I'm not getting any further.
I can specify other options here instead of array(), but I don't know how or which ones.

$this->pdf->TextField($param['name'], $w, $h, $prop, array(), $x, $y);

Of course, there may be another solution.

I would be very happy to find a solution here, because the feature is ideal for my purposes, since the text in the text field that I create in the PDF can be quite long.