On a fillable PDF, how do you enable text boxes to expand as text is typed?

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Working on a fillable PDF form, trying to get the text boxes to expand as needed when text is typed into them. I have set the boxes as Multi-line so you can format within the box, and text scrolls when box is filled, but I would like the box itself to expand so all text is viewable together, and also so that it will print and show all of the text. Thank you!