CSS: Print font colors in Firefox

Question

I'm trying to style a web page for printing. I want fonts to be printed in the original color. In Firefox fonts are always turn to black when printing. The setting of "Print Background (colors & images)" is turned on.

Any ideas?

Answer 1

I had success with the solution similar in Firefox 70.0.1 to that described by Plenarto.
However I needed to set the color to transparent for Firefox to print the text as white.

h1 {
    color: transparent;
    text-shadow: 0 0 0px #fff;
}