RichText link underline thickness varies

When an <a> tag is specified in a Text object using RichText format, the resulting link is underlined, but the thickness of the link varies, in my case between 1 or 2 pixels. It can even be different between two links in the same Text object. Furthermore, dynamically resizing the Text causes the thicknesses to toggle randomly. It would probably be enough to make all link underlines 1 pixel, but if that's insufficient for hi-res screens, the thickness should certainly be computed once based on font size and used consistently.