The font-size-adjust CSS property preserves the readability of text when font fallback occurs. It does this by adjusting the font-size so that the x-height is the same regardless of the font used.
object.style.fontSizeAdjust = "value";
<'font-size-adjust'> = none | <number>
Do not preserve the x-height.
An integer or zero or more decimal digits followed by a dot (.) followed by one or more decimal digits. The first character may be preceded by a sign (- or +). The last character may be succeeded by an exponent (e or E) and an integer.