How to make clear buttons (for TextField, TextArea, etc.) visible?

The clear button of TextField, TextArea, IntegerField, etc. are obviously hidden by default. I see that the corresponding JS-code is present in all these components but hidden is set to true.

I tried to make the visible via setClearButtonVisible(true) but that didn’t work. The clear buttons are NOT shown.
I also dislike that I would have to put these statements all over the place,
Can one not make these clear buttons also visible using styling only?

I tried to extend my “vaadin-text-field-styles.css” file with:
[part="clear-button"] { hidden: false; }

… but that didn’t show any effect. Am just doing it wrongly or is this not possible?